[21Vianet Group, Inc. Announces Strategic Joint Venture with Dongguan Government Beijing, September 4, 2013 — 21Vianet Group, Inc. (NASDAQ: VNET) (“21Vianet” or the “Company”), the largest carrier-neutral internet data center services provider in China, today announced that it has entered into a strategic joint venture with the Dongguan Municipal People’s Government in Guangdong province (“Dongguan Government”) to jointly build a] [FORM 6-K 21Vianet Group, Inc. M5, 1 Jiuxianqiao East Road, Chaoyang District Beijing 100016 The People’s Republic of China (86 10) 8456 2121 x ¨ Form 20-F ¨ ¨ 21Vianet Group, Inc. Shang-Wen Hsiao President and Chief Financial Officer 6-K 1 d594107d6k.htm FORM 6-K]

[21Vianet Group, Inc. Reports Unaudited Second Quarter 2013 Financial Results 2Q13 Net Revenues Up 29.3% YOY to RMB 471.1 Million 2Q13 Adjusted EBITDA Up 23.8% YOY to RMB87.2 Million Live Conference Call to be Held at 8:00 PM U.S. Eastern Time, August 20, 2013 BEIJING, Aug. 20, 2013 — 21Vianet Group, Inc. (Nasdaq: VNET) (“21Vianet” or the “Company”), the largest] [21Vianet Group, Inc. Shang-Wen Hsiao Chief Financial Officer 6-K 1 d586009d6k.htm FORM 6-K]

[21Vianet Group, Inc. Expands Leadership Team July 10, 2013 — 21Vianet Group, Inc. (NASDAQ: VNET) (“21Vianet” or the “Company”), the largest carrier-neutral internet data center services provider in China, today announced that its board of directors has appointed Mr. Frank Meng, a telecommunications and IT veteran with almost 30 years of experience, as President of the Company effective July 8,] [21Vianet Group, Inc. Shang-Wen Hsiao President and Chief Financial Officer 6-K 1 d568255d6k.htm FORM 6-K]

[21Vianet Group, Inc. Reports Unaudited First Quarter 2013 Financial Results 1Q13 Net Revenues Up 26.0% YOY to RMB435.7 Million 1Q13 Adjusted EBITDA Up 15.4% YOY to RMB80.1 Million Live Conference Call to be Held at 8:00 PM U.S. Eastern Time, May 16, 2013 Beijing, May 16, 2013—21Vianet Group, Inc. (NASDAQ: VNET) (“21Vianet” or the “Company”), the largest carrier-neutral internet data] [FORM 6-K 21Vianet Group, Inc. M5, 1 Jiuxianqiao East Road, Chaoyang District Beijing 100016 The People’s Republic of China (86 10) 8456 2121 x ¨ Form 20-F ¨ ¨ 21Vianet Group, Inc. Shang-Wen Hsiao President and Chief Financial Officer 6-K 1 d542858d6k.htm FORM 6-K]