<SUBMISSION>
<ACCESSION-NUMBER>0001193125-06-184359
<TYPE>424B3
<PUBLIC-DOCUMENT-COUNT>1
<FILING-DATE>20060901
<DATE-OF-FILING-DATE-CHANGE>20060901
<FILER>
<COMPANY-DATA>
<CONFORMED-NAME>PRO PHARMACEUTICALS INC
<CIK>0001133416
<ASSIGNED-SIC>2834
<IRS-NUMBER>043562325
<STATE-OF-INCORPORATION>NV
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>424B3
<ACT>33
<FILE-NUMBER>333-132459
<FILM-NUMBER>061071206
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>189 WELLS ST
<STREET2>STE 200
<CITY>NEWTON
<STATE>MA
<ZIP>02459
<PHONE>6175590033
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>189 WELLS ST
<STREET2>STE 200
<CITY>NEWTON
<STATE>MA
<ZIP>02459
</MAIL-ADDRESS>
</FILER>
<DOCUMENT>
<TYPE>424B3
<SEQUENCE>1
<FILENAME>d424b3.htm
<DESCRIPTION>FORM 424(B)(3)
<TEXT>
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<TITLE>Form 424(b)(3)</TITLE>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Filed Pursuant to Rule 424(b)(3) </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"
ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Registration No.&nbsp;333-132459 </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>PROSPECTUS SUPPLEMENT NO. 4 </B></FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>(to Prospectus dated March&nbsp;29, 2006, as supplemented by </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="2"><B>Prospectus Supplement No.&nbsp;1 dated May&nbsp;31, 2006, Prospectus Supplement No.&nbsp;2 </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>dated
June&nbsp;30, 2006, and Prospectus No.&nbsp;3 dated July&nbsp;27, 2006) </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="4"><B>PRO-PHARMACEUTICALS, INC. </B></FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>7,300,000 SHARES OF COMMON STOCK </B></FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><HR WIDTH="17%" SIZE="1" NOSHADE
COLOR="#000000"> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">This Prospectus Supplement No.&nbsp;4 supplements the Prospectus dated March&nbsp;29, 2006 (as supplemented by Prospectus Supplement
No.&nbsp;1 dated May&nbsp;31, 2006, Prospectus Supplement No.&nbsp;2 dated June&nbsp;30, 2006, and Prospectus No.&nbsp;3 dated July&nbsp;27, 2006) relating to the offer and sale of (i)&nbsp;up to 5,150,000 shares of our Common Stock, par value
$0.001 per share, issuable upon the conversion or redemption of, or as interest payments on, our 7% Convertible Debentures (the &#147;Debentures&#148;) and (ii)&nbsp;up to 2,150,000 shares of our Common Stock issuable upon the exercise of Common
Stock Purchase Warrants (the &#147;Warrants&#148;). We issued and sold the Debentures and Warrants on February&nbsp;14, 2006. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">The
Debentures state that we may elect to make redemption and interest payments thereunder in cash or shares of our Common Stock. On August&nbsp;28, 2006, we provided notice to the initial holders of the Debentures that we have elected to pay the
interest and principal due October&nbsp;1, 2006 in shares of our Common Stock. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">This prospectus supplement should be read in conjunction
with the Prospectus dated March&nbsp;29, 2006, which is to be delivered with this prospectus supplement. All capitalized terms used but not defined in this prospectus supplement shall have the meanings given them in the Prospectus. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>Investing in the shares of Common Stock issued pursuant to the Debentures or upon exercise of the Warrants involves substantial risks. See &#147;Risk
Factors&#148; beginning on page 4 of the Prospectus dated March&nbsp;29, 2006. </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">Our Common Stock is listed on the American Stock
Exchange under the symbol &#147;PRW&#148;. The last reported price of our Common Stock on August&nbsp;31, 2006 was $0.90 per share. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman"
SIZE="2"><B>Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined whether this prospectus supplement or the Prospectus is truthful or complete. Any
representation to the contrary is a criminal offense. </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">The date of this Prospectus Supplement No.&nbsp;4 is September&nbsp;1, 2006.
</FONT></P>
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</TEXT>
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</SUBMISSION>
