Exhibit 23.1
Consent of Independent Registered Public Accounting Firm
We consent to the incorporation by reference in the Registration Statement (FormS-8) pertaining to the 2014 Share Incentive Plan, as amended, of 21Vianet Group, Inc. of our reports dated April 12, 2017, with respect to the consolidated financial statements of 21Vianet Group, Inc. and the effectiveness of internal control over financial reporting of 21Vianet Group, Inc. included in its Annual Report (Form20-F) for the year ended December 31, 2016, filed with the Securities and Exchange Commission.
/s/ Ernst & Young Hua Ming LLP
Shanghai, People’s Republic of China
January 12, 2018