(VNET) Announces Change in Leadership Team

BEIJING, June 10, 2015  — 21Vianet Group, Inc. (Nasdaq:VNET) (“21Vianet” or the “Company”), a leading carrier-neutral internet data center services provider in China, today announced that Mr. Frank Meng, the president of the Company, will be leaving the Company to pursue other opportunities, effective immediately.

Mr. Josh Chen, Founder, Chairman and Chief Executive Officer of the Company, stated, “Mr. Meng has made an important contribution to 21Vianet since he joined us in July 2013. We thank him for his leadership and dedication to the Company. We wish him all the best in his future endeavors.”

Mr. Meng’s responsibilities have been delegated to and shared among 21Vianet’s existing senior management team.

About 21Vianet

21Vianet Group, Inc. is a leading carrier-neutral internet data center services provider in China. 21Vianet provides hosting and related services, managed network services, cloud services, content delivery network services, last-mile wired broadband services and business VPN services, improving the reliability, security and speed of its customers’ internet infrastructure. Customers may locate their servers and networking equipment in 21Vianet’s data centers and connect to China’s internet backbone through 21Vianet’s extensive fiber optic network. In addition, 21Vianet’s proprietary smart routing technology enables customers’ data to be delivered across the internet in a faster and more reliable manner. 21Vianet operates in more than 30 cities throughout China, servicing a diversified and loyal base of more than 2,000 customers that span numerous industries ranging from internet companies to government entities and blue-chip enterprises to small- to mid-sized enterprises.

Safe Harbor Statement

This announcement contains forward-looking statements. These forward-looking statements are made under the “safe harbor” provisions of the U.S. Private Securities Litigation Reform Act of 1995. These statements can be identified by terminology such as “will,” “expects,” “anticipates,” “future,” “intends,” “plans,” “believes,” “estimates” and similar statements. 21Vianet may also make written or oral forward-looking statements in its reports filed with, or furnished to, the U.S. Securities and Exchange Commission, in its annual reports to shareholders, in press releases and other written materials and in oral statements made by its officers, directors or employees to third parties. Further information regarding these and other risks is included in 21Vianet’s reports filed with, or furnished to, the Securities and Exchange Commission. All information provided in this press release and in the attachments is as of the date of this press release, and 21Vianet undertakes no duty to update such information, except as required under applicable law.

CONTACT: Investor Relations Contact:

         21Vianet Group, Inc.
         Eric Chu, CFA
         +1 (908) 707 2062
         IR@21Vianet.com

         Joseph Cheng
         +86 10 8456 2121
         IR@21Vianet.com

         ICR, Inc.
         Calvin Jiang
         +1 (646) 405-4922
         IR@21Vianet.com