Many prominent commentators and writers with influence over public opinion already post under their real names. For example, Pan Shiyi, a wealthy real estate developer who posts regularly, has more than seven million followers. He recently used his platform to advocate stricter air pollution reports from the Beijing government.

“In fact, serious weibo users have already opted to use their real names out of their own interests,” said another editor at Tencent who spoke on the condition of anonymity because of the sensitivity of talking about government policy.

Internet companies hosting microblogs have been told to comply with the new rules within three months. Sina and Tencent have more than 200 million registered users each; it is unclear how the companies will go about ensuring that each user has registered with real data.

But Mr. Bishop said the technology was already in place and had been used by one large Internet company, Baidu, when it ran its own version of a microblog, which no longer exists. The registration information that users enter online can be matched up against a police database, he said.

Leaders here have long discussed how to better control the Chinese Internet, which has about 485 million users, the most of any country. Most vexing for officials has been the speed with which information can spread on microblogs. This year, several episodes highlighted the reach of microblogs, including posts that ignited mass anger over both the Wenzhou high-speed train crash and the hit-and-run death of a 2-year-old toddler, Yueyue.

China has for years blocked Twitter and Facebook, and officials here carefully monitored the rebellions this year in the Middle East to see how they were organized and what role social networking sites played.

But Chinese officials also see the microblogs as useful. The sites allow people to vent anger, and officials can track posts to see the direction of public opinion. More and more officials are also being encouraged to use microblogs for propaganda and to mold discussions. Talk within the party about controlling the Internet accelerated after a policy meeting of the party’s Central Committee in October that focused on culture and ideology.

In the announcement Friday, Beijing officials said microblogs should “actively spread the core values of the socialist system, disseminate socialist advanced culture and build a socialist harmonious society.”