Scandal-tainted Chinese actress Zheng Shuang is at the centre of another controversy, this time over tax evasion, sky-high salary and contract fraud.

China's taxation and broadcasting watchdogs said on Wednesday (April 28) that they are investigating the 29-year-old star, who has seen her promising career derailed by accusations that she had abandoned two surrogate children in the United States three months ago.

Now, the Shanghai Municipal Tax Service is conducting an investigation into her tax issues, while the Beijing Municipal Radio and Television Bureau has launched a probe into the production costs of television series and how much she was paid.

On Monday, her former partner, producer Zhang Heng, 30, released screenshots of alleged chats between him, Zheng and her parents.

They were discussing Zheng's payment from the upcoming drama A Chinese Ghost Story and the screenshots allegedly show Zheng had negotiated to be paid 160 million yuan (S$32.7 million) for 77 days of filming.

Her huge paycheque provoked outrage from netizens, who calculated that an average worker would have to work more than 2,222 years, starting from the Qin dynasty (221 to 206 BC), to make that amount.

In addition, her alleged salary also violates China's National Radio and Television Administration's rules, which say actors in movies and TV shows should not be paid more than 40 per cent of production cost, with the main actors less than 70 per cent of the total cost.

Also, an actor should not be paid more than 50 million yuan per show.

In order to get around these rules, Zheng allegedly signed two contracts - one which stated her pay as 48 million yuan and another with the rest of her money going to a company connected to her family as investment.

Besides accusing Zheng of fraud, Zhang also revealed in his post that she would eat snacks in the supermarket and leave without paying.

He also alleged that she had abandoned her sick dog in a shoe box because she didn't want to pay for the treatment, which cost 2,000 yuan.