Press Release Details

January 17, 2014, Beijing-21Vianet Group, Inc. (NASDAQ: VNET) ("21Vianet" or the "Company"), the largest carrier-neutral internet data center services provider in China, today announced that the Company was granted the Trustworthy Cloud Service certification by the Ministry of Industry and Information Technology ("MIIT"). 21Vianet was among the first few companies in China which received the Trustworthy Cloud Service certification.

In an effort to improve the security and stability of cloud services in China, the MIIT conducted China's first certification review evaluating the security and trustworthiness of various cloud service solutions in 2013. The MIIT granted the certificate to 21Vianet upon completion of a stringent evaluation process which analyzed its cloud services on 16 sets of criteria defined in the international standards of the Service Level Agreement (SLA) including: efficiency of data management, quality of service, and level of intellectual property right protection.

Structured on an open platform, 21Vianet's cloud services proved to meet the rigorous SLA standards in terms of stability and security. Specifically, 21Vianet's Windows Azure guarantees service uptime of up to 99.95%, providing customers with the most comprehensive and secure disaster recovery service and allowing a high level of interoperability that supports the exchange of customer data over various programming languages and operating systems.

Mr. Wing-Dar Ker, president of 21Vianet's Microsoft Cloud Operation, stated: "As the leading carrier-neutral internet infrastructure and data center services provider in China, receiving this certification from China's state technology authority is a testament to our success, leadership and importance in the development of China's cloud computing industry. 21Vianet, together with Microsoft China, is committed to bringing high-quality, trustworthy cloud service solutions to users in China by emphasizing improved stability, security and network quality. With our recognized market leadership, operational expertise and expanding service offering, we're confident that 21Vianet is poised to capitalize on the growth opportunities in China's burgeoning cloud computing industry."

About 21Vianet
21Vianet Group, Inc. is the largest carrier-neutral internet data center services provider in China. 21Vianet provides hosting and related services, managed network services, cloud infrastructure services, and content delivery network 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 44 cities throughout China, servicing a diversified and loyal base of more than 2,000 customers that span many 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. Among other things, the quotations from management in this announcement, as well as 21Vianet's strategic and operational plans, contain forward-looking 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. Statements that are not historical facts, including statements about 21Vianet's beliefs and expectations, are forward-looking statements. Forward-looking statements involve inherent risks and uncertainties. A number of factors could cause actual results to differ materially from those contained in any forward-looking statement, including but not limited to the following: 21Vianet's goals and strategies; 21Vianet's expansion plans; the expected growth of the data center services market; expectations regarding demand for, and market acceptance of, 21Vianet's services; 21Vianet's expectations regarding keeping and strengthening its relationships with customers; 21Vianet's plans to invest in research and development to enhance its solution and service offerings; and general economic and business conditions in the regions where 21Vianet provides solutions and services. Further information regarding these and other risks is included in 21Vianet's reports filed with, or furnished to the Securities and Exchange Commission. 21Vianet does not undertake any obligation to update any forward-looking statement, except as required under applicable law. 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.

Investor Relations Contact:

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

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