EXHIBIT 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Registration Statement (Form S-8) pertaining to the Second Amendment to the 2011 Stock Incentive Plan of Peregrine Pharmaceuticals, Inc. of our reports dated July 11, 2013, with respect to the consolidated financial statements and schedule of Peregrine Pharmaceuticals, Inc. and the effectiveness of internal control over financial reporting of Peregrine Pharmaceuticals, Inc., included in its Annual Report (Form 10-K) for the year ended April 30, 2013, filed with the Securities and Exchange Commission.

/s/ Ernst & Young LLP       

Irvine, California

December 11, 2013