The actor's body was discovered inside his North Hollywood home on Monday with a self-inflicted gunshot wound, TMZ reported.
It's unclear why Young killed himself.
"It is with great sadness that I announce that Lee Thompson Young tragically took his own life this morning ... Lee was more than just a brilliant young actor, he was a wonderful and gentle soul who will be truly missed," his publicist said.
The actor was working on show "Rizzoli & Isles". The staffers apparently called his landlord and told him to check up after Young did not -- and we're told when he didn't show up to work Monday morning, staffers called Young's landlord to check up on the actor.