The fan club for 50-year-old Peng on the microblog platform Weibo, China's equivalent of Twitter had attracted more than 5,600 followers before it was suspended on Tuesday, up from fewer than 1,000 last week.
"Sorry, the account you are visiting is abnormal and cannot be accessed temporarily," was the message that greeted people trying to reach the Guo Mu (mother of the nation) fan club.
The club was created by Wang Jian, 28, a student at Xiamen University, who described the censors' action as "undemocratic". He said that he did not receive any notice before the microblog was shut down.
"There's nothing sensitive [on the site]," Wang said. "If it is because of the name Guo Mu, they should have let me know before suspending my account because there's no specific rule against it," he was quoted as saying by the Hong Kong based South China Morning Post.
Wang said he spent much of his spare time working on the fan site, which featured old photos of Peng, videos of her performances as a folksinger in a career spanning 30 years, and photos of Xi and Peng together.