The son of famed wrestler Jerry Lawler tried to hang himself Saturday night and he is now on life support ... TMZ Sports has learned.

Brian Christopher Lawler, once a wrestler himself, attempted to commit suicide in his jail cell outside Memphis 

TMZ Sports broke the story ... Brian was arrested earlier this month for DUI after leading cops on a chase.

The 46-year-old, who went by Grandmaster Sexay in the WWE, was found in his cell by guards and taken to a hospital ... where he was placed on life support. 

Brian remains in critical condition, a hospital spokesperson confirms to TMZ Sports.

In his wrestling days, Lawler teamed up with Scotty 2 Hotty and the 2 became extremely popular as the duo "Too Cool," winning a tag team championship. 

We've reached out to Jerry Lawler and his family ... so far, no word back.

Story developing ...