A Chinese man has dressed as a woman for 20 years to help his mentally ill mother cope with the death of his sister.

The unnamed man, from Guilin in the Guangxi region, is seen wearing a traditional cheongsam dress while looking after his elderly mother in a video about his story.

He said he started dressing as a woman after his mother began showing signs of mental illness following the death of her daughter.

"The first time I dressed as a woman she was so happy, so I kept doing it," he told Pear Video, whose film has been watched more than 4.2 million times and been shared widely in China.

"I've basically been living as a woman ever since. I don't own any men's clothing."