Wang Xiaomeng, 23, tweeted three pictures of herself on Sina Weibo, China's version of Twitter, in July.
One of the photographs showed her sitting on a bed, her top half fully clothed in a light blue police shirt and jaunty hat, but her legs bare as she pulled on a set of standard issue black tights.
Together with the photographs, she wrote a playful scenario.
"As a new cop in my hometown, I need to learn the basics. As one of the flowers of the force, I am under pressure. I have to eat and drink with government leaders every day. I am using my flower status to dine with the leaders and win contracts for projects and investments!"
Her posts were retweeted more than 500 times and attracted 300 comments, most of them critical. She deleted them shortly afterwards and no one appears to have been fooled into thinking she was a real policewoman.
However, the government took a dim view. Sina, the internet company that runs Weibo, said it was a "deliberate attempt at self promotion" after receiving 14 complaints.
The following day, Ms Wang, received a call from the police.
"The costume was just a prop, I was so ignorant," she said, in her defence, explaining that the photographs were taken for an advertisement and she had been paid 3,000 yuan (£300). She said she decided to post them on the internet to attract more commissions and followers.
A court in Fengtai, Beijing, found her guilty of falsely impersonating a policewoman on Monday and sentenced her to nine months in prison, suspended for a year.
