BEIJING — In what has been described as China’s first case involving transgender discrimination in the workplace, a court in the southwestern province of Guizhou has ruled that the plaintiff was illegally fired but that there was no proof that his dismissal was a result of bias against transgender people.

“We found this a little bit of a shame,” Huang Sha, the lawyer for the plaintiff, a 28-year-old transgender man who has been identified in the state news media only as “Mr. C” and who has declined to provide his real name to protect his privacy, said in a telephone interview.

Mr. C, who was born a woman but says he has long considered himself a man, was dismissed from the Ciming Health Checkup Center in Guiyang, the provincial capital, in April 2015 after a one-week probation. In March 2016, Mr. C filed his case with a local labor arbitration committee asking for compensation and a written apology. Mr. C said in an interview in April that the company’s human resources manager had complained that he dressed like a gay man and looked too “unhealthy” to be an employee for a health checkup company.

In May, the arbitration committee ordered the company to pay Mr. C 402.30 renminbi, about $61 at the time, for the probation period, but rejected his demand for an additional month’s pay of 2,000 renminbi and an apology. He and Mr. Huang then brought the case to court.