LeBron James has one thing on his mind right now, and it sure as hell ain't Michael Jordan ... so says M.J.'s former teammate, Charles Oakley, who tells TMZ Sports the King only cares about beating the Warriors.

Oak -- who's good friends with LBJ -- gave us a bit of insight on what's going through LBJ's head during the playoffs, and the fellow Cleveland native says James only cares about getting that 4th ring.

As for LeBron's chances against the Warriors -- who have yet to lose a game in the playoffs -- Oak's confident the Cavs are gonna come out on top.