Lark Voorhies' Mom -- My Son-in-Law Is a Gang Member ... Who Sleeps in My Closet

"Saved by the Bell" star Lark Voorhies' new husband is seriously bad news, as in ... he's a member of the Bloods who's been threatening his mother-in-law -- this according to Lark's mother.

Patricia Voorhies filed a restraining order against Jimmy Green ... saying he throws gang signs at her while arguing with her -- and it sounds like they argue a lot because he's shacking up with Lark under Mom's roof.

Patricia says after Lark and Jimmy tied the knot -- the deal was Green would be out of the house every evening in time to catch the last bus back to his place, but instead she kept finding him asleep in the house ... including one time in a closet. She says Green yelled, "You motherf**king woke me up, ain't that a bitch."

Lark's mom also points out Lark is mentally and emotionally fragile and under doctors' care.

Patricia was granted a temporary restraining order to keep Jimmy 100 yards away from her and her home.