An official from north China's Shanxi province thought that he bought his mistress' silence by paying her a hefty amount after the break-up.
But the mistress went on to post the "termination agreement" online, Beijing News reported.
The report said that Xiaoyi municipal environmental protection bureau official Guo Shuanglong signed an agreement with his 26-year-old mistress.
He paid her 400,000 yuan (S$82,000) to end their relationship.
The agreement, signed by the ex-couple, shows how Mr Guo attempted to break up with his mistress in July last year.
She refused and allegedly began harassing him and his family.
Last month, Mr Guo tried to break up again and succeeded.
The mistress agreed to stop the harassment of Mr Guo and his family.
Another official, surnamed Su, even signed the document as a witness, Hong Kong daily South China Morning Post reported.
Mr Su, a local village head, reportedly confirmed the existence of the agreement to Beijing News.
It is not known whether Mr Guo has been sacked or any disciplinary action taken against him.
In the past six months, five provincial leaders have been sacked, including four from the local party committee.
On Sunday, a city level official fell to his death following questioning by anti-corruption investigators, business and news website Caixin reported.
Reports said he had been questioned twice by the provincial discipline inspection committee.
While the cause of his fall has not been confirmed, it is not uncommon for those under investigation for corruption to commit suicide rather than face disgrace and trial.
Around 30 officials have killed themselves so far this year, according to researchers at Shanghai's East China Normal University and Beihang University.
This article was first published on Sept 17, 2014.
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