Exhibit 23.2 Consent of Deloitte & Touche, LLP, Independent Registered Public Accounting Firm CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM We consent to the incorporation by reference in this Registration Statement of Ligand Pharmaceuticals Incorporated on Form S-8 of our report dated March 10, 2004 (which report expresses an unqualified opinion and includes an explanatory paragraph referring to a change in accounting principle), appearing in the Annual Report on Form 10-K of Ligand Pharmaceuticals Incorporated for the year ended December 31, 2003. San Diego, California July 1, 2004