After the Jul 2009 Ürümqi riots, China shut down most domestic microblogging services, including Fanfou, the very first weibo service. Many popular non-China-based microblogging services like Twitter, Facebook, and Plurk have since been blocked.
Sina Corporation CEO Charles Chao considered this to be an opportunity, and on 14 Aug 2009, Sina launched the tested version of Sina Weibo.
On 1 Dec 2010, the website experienced an outage, which administrators later said was due to the ever-increasing numbers of users and posts. Registered users surpassed 100M in Feb 2011.
On 7 Apr 2011, weibo.com replaced t.sina.com.cn as the new main domain name used by the website.
In Jun 2011, Sina released an English-language version of Sina Weibo in which content would be monitored by Chinese law.