Exhibit 15.1
Consent of Independent Registered Public Accounting Firm
We consent to the incorporation by reference in the Registration Statement (Form S-8 No.
333-150656) pertaining to the 2001 Siemens Stock Option Plan, Siemens Stock Awards, Siemens Saving
Plan and Siemens Savings Plan for Union Employees, in the Registration Statement (Form S-8 No.
333-155888) pertaining to the Siemens Group Share Matching Plan and in the Registration Statement
(Form S-8 No. 333-163522) pertaining to the Siemens Savings Plan and the Siemens Savings Plan for
Union Employees of our reports dated November 25, 2010 with respect to the consolidated financial
statements of Siemens Aktiengesellschaft and the effectiveness of internal control over financial
reporting of Siemens Aktiengesellschaft in this Annual Report (Form 20-F) for the year ended
September 30, 2010.
/s/ Ernst & Young GmbH
Wirtschaftsprüfungsgesellschaft
Munich, Germany
December 2, 2010