-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 DvoVTkFlc+FL28Fsa4xrfLKMnUnwGMVli9Q8Z7rUXP5rNJ859kE28uNU1KqgG3id
 Buwuwvx2H7t177ROE3BeJg==

<SEC-DOCUMENT>0001292814-10-001382.txt : 20100507
<SEC-HEADER>0001292814-10-001382.hdr.sgml : 20100507
<ACCEPTANCE-DATETIME>20100507135626
ACCESSION NUMBER:		0001292814-10-001382
CONFORMED SUBMISSION TYPE:	6-K
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100630
FILED AS OF DATE:		20100507
DATE AS OF CHANGE:		20100507

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NATIONAL STEEL CO
		CENTRAL INDEX KEY:			0001049659
		STANDARD INDUSTRIAL CLASSIFICATION:	STEEL WORKS, BLAST FURNACES & ROLLING & FINISHING MILLS [3310]
		IRS NUMBER:				000000000
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		6-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14732
		FILM NUMBER:		10811552

	BUSINESS ADDRESS:	
		STREET 1:		RUA LAURO MULLER
		STREET 2:		116 36 ANDAR
		CITY:			RIO DE JANEIRO RJ BR
		STATE:			D5
		ZIP:			00000
</SEC-HEADER>
<DOCUMENT>
<TYPE>6-K
<SEQUENCE>1
<FILENAME>sid20100507_6k.htm
<DESCRIPTION>NOTICE TO THE MARKET
<TEXT>

<HTML>
<HEAD>
   <TITLE>sid20100507_6k.htm - Provided by MZ Technologies</TITLE>
</HEAD>

<BODY bgcolor="#ffffff" style="font-family: 'Times New Roman';font-size: 9pt;">

<HR align=left color=#000000 noShade SIZE=4>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=5><B>SECURITIES AND EXCHANGE COMMISSION </B></FONT></DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=3><B>Washington, D.C. 20549 </B></FONT></DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<HR align=center width="21%" color=#000000 noShade>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=5><B>FORM 6-K </B></FONT></DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=3>Report of Foreign Private Issuer<BR>
Pursuant to Rule 13a-16 or 15d-16 of the</FONT></DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=3>Securities Exchange Act of 1934</FONT></DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV align=center>
<DIV><FONT face="Times New Roman" color=#000000 size=3><B>For the month of May, 2010</B></FONT></DIV>
<P></P>
<FONT face="Times New Roman" color=#000000 size=3><B>Commission File Number 1-14732 </B></FONT></DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<HR align=center width="21%" color=#000000 noShade>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=5><B>COMPANHIA SIDER&#218;RGICA NACIONAL </B></FONT></DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=2>(Exact name of registrant as specified in its charter) </FONT></DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV align=center></DIV>
<P></P>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=5><B>National Steel Company </B></FONT></DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=2>(Translation of Registrant's name into English)</FONT></DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<P></P>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=3><B>Av. Brigadeiro Faria Lima 3400, 20&#186; andar<BR>
S&#227;o Paulo, SP, Brazil<BR>
04538-132 </B></FONT></DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=2>(Address of principal executive office)</FONT></DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=3>Indicate by check mark whether the registrant files or will file annual reports<BR>
under cover Form 20-F or Form 40-F.&nbsp;</FONT>
<P></P>
Form 20-F ___X___ Form 40-F _______
<P>&nbsp;<FONT face="Times New Roman, Times, Serif" size=3>Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934. </FONT>&nbsp;</P>
Yes _______ No ___X____
<P></P>
</DIV>
<HR align=left color=#000000 noShade SIZE=2>
<H5 style="PAGE-BREAK-BEFORE: always" align=left></H5>
<A name="page_1"></A>
<DIV style="PADDING-RIGHT: 0%; PADDING-LEFT: 0%">
<DIV>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=PT-BR style="FONT-SIZE: 10pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
</DIV>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: center" align=center><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">NOTICE TO THE MARKET</FONT></B></P>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: center" align=center><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">COMPANHIA SIDER&#218;RGICA NACIONAL</FONT></P>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: center" align=center><FONT lang=PT-BR style="FONT-SIZE: 10pt" face="Times New Roman,serif">Rua S&#227;o Jos&#233; n&#186; 20, Grupo 1602, parte</FONT></P>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: center" align=center><FONT lang=PT-BR style="FONT-SIZE: 10pt" face="Times New Roman,serif">Rio de Janeiro/RJ</FONT></P>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: center" align=center><FONT lang=EN-US style="FONT-SIZE: 10pt" face="Times New Roman,serif">Corporate Taxpayer's ID (CNPJ/MF):&nbsp; 33.042.730/0001-04</FONT></P>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT></B>&nbsp;</P>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT></B>&nbsp;</P>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">The Board of Directors of COMPANHIA SIDER&#218;RGICA NACIONAL authorized, on May 6, 2010, a new share buyback program (&#147;Share Buyback Program&#148;), which will be held in treasury for subsequent sale or cancellation.</FONT></P>
<H1 style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><B><FONT style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT></B>&nbsp;</H1>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">The Share Buyback Program shall respect the following limits and conditions, pursuant to the provisions of CVM Instructions 10/80 and 358/2002:</FONT></P>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<OL style="MARGIN-TOP: 0in; MARGIN-BOTTOM: 0in" type=I>
<LI style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">The Company&#146;s objective: </FONT></B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">to maximize the creation of value to shareholders by means of an efficient capital structure management and the follow-up of&nbsp; market volatility.</FONT> </LI></OL>
<P style="MARGIN: 0in 0in 0pt 0.5in; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<OL style="MARGIN-TOP: 0in; MARGIN-BOTTOM: 0in" type=I start=2>
<LI style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">Number of shares to be acquired: </FONT></B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">up to 28,874,810 shares.</FONT> </LI></OL>
<P style="MARGIN: 0in 0in 0pt 0.5in; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<OL style="MARGIN-TOP: 0in; MARGIN-BOTTOM: 0in" type=I start=3>
<LI style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">Effective period for performing authorized transactions: </FONT></B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">from May 7, 2010 to June 8, 2010, inclusively.</FONT> </LI></OL>
<P style="MARGIN: 0in 0in 0pt 0.5in; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<OL style="MARGIN-TOP: 0in; MARGIN-BOTTOM: 0in" type=I start=4>
<LI style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">Free float: </FONT></B><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="Times New Roman,serif">812,639,230 </FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">shares.</FONT> </LI></OL>
<P style="MARGIN: 0in 0in 0pt 0.5in; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<OL style="MARGIN-TOP: 0in; MARGIN-BOTTOM: 0in" type=I start=5>
<LI style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">Place of Acquisitions: </FONT></B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">Stock Exchange.</FONT> </LI></OL>
<P style="MARGIN: 0in 0in 0pt 0.5in; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<OL style="MARGIN-TOP: 0in; MARGIN-BOTTOM: 0in" type=I start=6>
<LI style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">Maximum Share Price: s</FONT></B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">hare acquisition price cannot exceed its market price.</FONT> </LI></OL>
<P style="MARGIN: 0in 0in 0pt 0.5in; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<OL style="MARGIN-TOP: 0in; MARGIN-BOTTOM: 0in" type=I start=7>
<LI style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><B><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="Times New Roman,serif">Brokers: </FONT></B><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="Times New Roman,serif">Ita&#250; Corretora de Valores S.A., located at Av. Engenheiro Armando de Arruda Pereira, 707 -15&#186; andar- in the city of S&#227;o Paulo, UBS Pactual Corretora de Mercadorias Ltda., located at Av. </FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">Brigadeiro Faria Lima, 3729 &#150; 10&#186; andar &#150; in the city of S&#227;o Paulo, and Ita&#250; USA Securities Inc., located at 540 Madison Avenue - 23<SUP>rd</SUP> Floor- in New York city.</FONT> </LI></OL>
<P style="MARGIN: 0in 0in 0pt 0.5in; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<OL style="MARGIN-TOP: 0in; MARGIN-BOTTOM: 0in" type=I start=8>
<LI style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif">The Board of Directors has entrusted the Company&#146;s Board of Executive Officers to take all necessary measures to implement the resolution, including the establishment of the most convenient date to start the share buyback.</FONT> </LI></OL>
<P style="MARGIN: 0in 0in 0pt 0.5in; TEXT-ALIGN: justify"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 0pt 28.35pt; TEXT-INDENT: -28.35pt; TEXT-ALIGN: justify"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT></B>&nbsp;</P>
<H3 style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: center"><FONT lang=PT-BR style="FONT-WEIGHT: normal; FONT-SIZE: 12pt" face="Times New Roman,serif">Rio de Janeiro, May 7, 2010.</FONT></H3>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<H2 style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: center"><B><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="Times New Roman,serif">Companhia Sider&#250;rgica Nacional</FONT></B></H2>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: center" align=center><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="Times New Roman,serif">Paulo Penido Pinto Marques</FONT></P>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: center" align=center><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="Times New Roman,serif">Investor Relations Executive Officer</FONT></P>
<P style="MARGIN: 0in 0in 0pt; TEXT-ALIGN: center" align=center><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
<DIV>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=PT-BR style="FONT-SIZE: 10pt" face="Times New Roman,serif"></FONT>&nbsp;</P>
</DIV></DIV> <H5 style="PAGE-BREAK-BEFORE: always" align=left></H5>
<HR align=left color=#000000 noShade SIZE=2>
<P><FONT size=1></FONT>&nbsp;</P>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=3><B>SIGNATURE </B></FONT></DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV style="TEXT-INDENT: 4%"><FONT face="Times New Roman" color=#000000 size=3>Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. </FONT></DIV>
<P></P>
<DIV style="TEXT-INDENT: 4%"><FONT face="Times New Roman" color=#000000 size=3>Date: May 07, 2010</FONT></DIV>
<P></P>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV align=center>
<TABLE cellSpacing=0 cellPadding=0 width="50%" border=0>
<TR>
     <TD vAlign=top width="50%" colSpan=2>
<DIV align=left><FONT face="Times New Roman" color=#000000 size=3>COMPANHIA SIDER&#218;RGICA NACIONAL </FONT></DIV></TD></TR>
<TR>
     <TD width="50%" colSpan=2 height=16></TD></TR>
<TR>
     <TD vAlign=top width="5%">
<DIV align=left><FONT face="Times New Roman" color=#000000 size=2>By:</FONT></DIV></TD>
     <TD vAlign=bottom align=center width="45%">
<DIV align=center><FONT face="Times New Roman" color=#000000 size=2>/<SMALL>S</SMALL>/&nbsp;Benjamin Steinbruch </FONT></DIV>
<HR align=left color=#000000 noShade SIZE=1>
</TD></TR>
<TR>
     <TD width="5%"><FONT size=1>&nbsp;</FONT></TD>
     <TD vAlign=bottom align=center width="45%">
<DIV align=left><FONT face="Times New Roman" color=#000000 size=2><B>Benjamin Steinbruch </B></FONT></DIV>
<DIV align=left><FONT face="Times New Roman" color=#000000 size=2><B>Chief Executive Officer <BR>
<BR>
</B></FONT></DIV></TD></TR></TABLE></DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<P>&nbsp;</P>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV align=center>
<TABLE cellSpacing=0 cellPadding=0 width="50%" border=0>
<TR>
     <TD vAlign=top width="50%" colSpan=2>
<DIV align=left>&nbsp;</DIV></TD></TR>
<TR>
     <TD width="50%" colSpan=2 height=16></TD></TR>
<TR>
     <TD vAlign=top width="5%">
<DIV align=left><FONT face="Times New Roman" color=#000000 size=2>By:</FONT></DIV></TD>
     <TD vAlign=bottom align=center width="45%">
<DIV align=center><FONT face="Times New Roman" color=#000000 size=2>/<SMALL>S</SMALL>/&nbsp;Paulo Penido Pinto Marques </FONT></DIV>
<HR align=left color=#000000 noShade SIZE=1>
</TD></TR>
<TR>
     <TD width="5%"><FONT size=1>&nbsp;</FONT></TD>
     <TD vAlign=bottom align=center width="45%">
<DIV align=left><FONT face="Times New Roman" color=#000000 size=2><B>Paulo Penido Pinto Marques </B></FONT></DIV>
<DIV align=left><FONT face="Times New Roman" color=#000000 size=2><B>Chief Financial Officer and Investor Relations Officer<BR>
<BR>
</B></FONT></DIV></TD></TR></TABLE></DIV>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<P>&nbsp;</P>
<DIV><FONT size=1></FONT>&nbsp;</DIV>
<DIV align=center><FONT face="Times New Roman" color=#000000 size=3><B>FORWARD-LOOKING STATEMENTS </B></FONT></DIV>
<P align=justify><FONT face="Times New Roman, Times, Serif" size=2>This press release may contain forward-looking statements. These statements are statements that are not historical facts, and are based on management's current view and estimates of future economic circumstances, industry conditions, company performance and financial results. The words "anticipates", "believes", "estimates", "expects", "plans" and similar expressions, as they relate to the company, are intended to identify forward-looking statements. Statements regarding the declaration or payment of dividends, the implementation of principal operating and financing strategies and capital expenditure plans, the direction of future operations and the factors or trends affecting financial condition, liquidity or results of operations are examples of forward-looking statements. Such statements reflect the current views of management and are subject to a number of risks and uncertainties. There is no guarantee that the expected events, trends or 
results will actually occur. The statements are based on many assumptions and factors, including general economic and market conditions, industry conditions, and operating factors. Any changes in such assumptions or factors could cause actual results to differ materially from current expectations. </FONT></P>
<HR align=left color=#000000 noShade SIZE=2>
</BODY>

</HTML>

</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
