LeBron James Renovating New $23 Mil Brentwood Home

LeBron James is making his already incredible home even more fit for a king ... 'cause the NBA superstar is adding some crazy renovations to his new Brentwood mansion, TMZ Sports has learned.

ICYMI -- LBJ bought the 15,846 square foot house back in December for $23 mil ... and it came with a theater room, wine cellar, cigar room with air purifying technology and an onyx bar.

But, King James is takin' it even further ... our sources tell us he's adding a basketball court, indoor wine tap (dude LOVES his wine), and is working on the paperwork to get a pizza oven ... while also making changes to the theater and pool.

Remember ... this is LBJ's 2nd Brentwood mansion. After all, he spends his offseasons in L.A. working on his entertainment career (and might be here year-round next season, right Laker fans?).