Dusa Pharmaceuticals (DUSA) S-8 POS Registration of securities for employees (post-effective amendment)

EXHIBIT 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Post-Effective Amendment No. 1 to Registration Statement on Form S-8 (File No. 333-155431) of our report dated March 11, 2009, relating to the consolidated financial statements of DUSA Pharmaceuticals, Inc. (which report expresses an unqualified opinion and includes an explanatory paragraph relating to the adoption of Financial Accounting Standards Board (FASB) Interpretation No. 48,Accounting for Uncertainty in Income Taxes, an Interpretation of FASB Statement No. 109), appearing in this Annual Report on Form 10-K of DUSA Pharmaceuticals, Inc. for the year ended December 31, 2008, and to the reference to us under the heading “Experts” in the Prospectus, which is part of such Registration Statement.

/s/ DELOITTE & TOUCHE LLP

Boston, Massachusetts
August 17, 2009