"The spread of pornographic novels has disturbed the order of online publishing and disrupted social order," the General Administration of Press and Publication said in a statement.
The Xinhua news agency reported a state press watchdog said these websites cause great harm to the psychological development of young people.
The sites' sexual content violated several state Internet laws, which ban anything considered pornographic from being posted online. In recent months the government has claimed pornographic websites entice children to commit crimes.
The government launched a full-on campaign against online adult content in April, slated to last six months.
Xinhua reported that in about a month, 270 people were arrested in connection with online pornography.
"The boom of pornographic content on the Internet has contaminated cyberspace and perverted China's young minds," said Zhang Xinfeng, a deputy public security minister.
