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                                                                    EXHIBIT 23.1

The consolidated financial statements give effect to a 2-for-3 reverse stock
split of the outstanding common stock of IPG Photonics Corporation which will
take place prior to the effective date of the registration statement. The
following consent is in the form which will be provided by Deloitte & Touche
LLP, an independent registered public accounting firm, upon the completion of
the 2-for-3 reverse stock split of the Company's outstanding common stock as
described in Note 1 to the consolidated financial statements and assuming that
from November 22, 2006 to the date of such completion no other material events
have occurred that would affect the consolidated financial statements or
disclosure therein.

/s/ DELOITTE & TOUCHE LLP
--------------------------

Boston, Massachusetts
December 1, 2006



            "CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the use in this Amendment No. 5 to Registration Statement No.
333-136521 of our report dated November 13, 2006 (                  as to the
third paragraph of Note 1 and November 22, 2006 as to the third paragraph of
Note 11) (which report expresses an unqualified opinion and includes an
explanatory paragraph as to the adoption of Statement of Financial Accounting
Standards No. 123(R), "Share-Based Payment," effective January 1, 2006),
relating to the financial statements of IPG Photonics Corporation and
subsidiaries appearing in the Prospectus, which is part of such Registration
Statement, and to the reference to us under the heading "Experts" in such
Prospectus.

Boston, Massachusetts
             , 2006"


