The bureau said it had launched an investigation as the unapproved segment was suspected of violating regulations on commercial performances.
“The matter will subsequently be handled in accordance with laws and regulations,” it said.
A household name in China, Guo, 53, is known for his xiangsheng (crosstalk in Mandarin) comedy. He has 72.4 million followers on Chinese microblogging platform Weibo.
Guo has not posted on his public Weibo page since Aug 9.
His performance on Jul 24 has sparked discussion on social media, with clips posted online.
Hu Xijin, the former top editor of state-linked Global Times, was among those who weighed in on the debate.
In a Weibo post on Aug 13, Hu said he had felt “uncomfortable hearing a revolutionary song adapted and sung through the mouth of Ji Gong”.
“I thought it was inappropriate. But how serious is this matter, how should it be characterised, and how should it be dealt with?” he wrote.
As investigations were still ongoing, Hu called on the public to “respect” the bureau’s eventual findings and its decision on any penalties given.
