One of China's most famous actresses, Fan Bingbing, has been ranked last in a list of celebrities for their social responsibility, raising further questions about her sudden disappearance.

Key points: Fan Bingbing scored 0 per cent in a social responsibility rating

Fan Bingbing scored 0 per cent in a social responsibility rating The actress has not been seen since July

The actress has not been seen since July She is best known outside China for her roles in the X-Men films

The 2017-18 China Film and Television Star Social Responsibility Report ranks Chinese celebrities according to three criteria: professional work, charitable actions and personal integrity, state media reported.

A list of the rankings from the report published by state media outlet China Daily showed Bingbing received a score of 0 per cent.

According to the ranking list, only nine celebrities received a passing score of 60 per cent — including Bingbing's fiance, actor Li Chen.

The report was authored by the China Social Responsibility 100 Forum, which is said to have been established by experts, entrepreneurs and social activists.

Top of the list is actor Xu Zheng, with a score of 78 per cent.

Bingbing, who is best known in the West for her roles in the X-Men movie franchise, has not been seen in public since July 1, sparking rumours she is in prison.

She was publicly linked to a tax evasion investigation in May, and has since gone silent.

Last week, a state media report from China's state-run Securities Daily said that BingBing, 36, was "placed under control".

But the online story vanished not long after it first appeared.

Independent film critic Jiang Yong, based in Beijing, said Bingbing was the face of film, television and commercials in China.

"She's one of the most important celebrities in China, quite possibly the most famous," Mr Yong said.

Forbes named Bingbing first for the fourth consecutive year in its annual China Celebrity List in 2017.

Fan Bingbing (left) celebrates her best actress award at the Asian Film Awards in 2017. ( Reuters: Bobby Yip )

Authorities haven't confirmed she is being targeted in a tax investigation, but Mr Yong said it has been rumoured online that she's among the stars accused of using "Yin and Yang contracts".

"Yin and Yang contracts mean one contract is submitted to the tax department," Mr Yong said.

"But there's actually a second contract containing a higher amount of money that is the real contract.

"The tax department is now investigating this practice in the Chinese film industry."

The scandal has prompted Chinese regulators to cap the amount film studios can pay top stars.

Bingbing's spokesperson has denied any wrongdoing but has not addressed the specific allegations about dual contracts.

Well-known actor Jackie Chan has denied allegations he advised Bingbing to seek refuge in the US in the wake of China's ongoing tax evasion scandal.

Bingbing has previously been seen in Melbourne alongside Hugh Jackman for her role in X-Men.