He’s straight outta private school.

Lil Mabu — a drill rapper who has amassed 2.6 million followers by dropping beats about fighting cops, knocking over jewelry stores, and sleeping with “b—hes” — is actually a silver-spoon child of privilege.

He’s a senior at Collegiate School, the nearly 400-year-old Manhattan prep that costs $60,000 a year and has schooled generations of Vanderbilts and Kennedys.

The 17-year-old rapper’s real name is Matthew Peter DeLuca, and he lives at his parents’ five-bed, five-bath, 3,327-square foot condo on the Upper East Side. During school breaks or on weekends, he can escape the Hamptons, where his family owns a 6,182-square foot manse in Water Mill. The two properties are worth close to $12 million total.

Drill rap, a controversial sub-genre which glorifies guns, drugs and violence, has developed a following in recent years among young people. Last February, 18-year-old drill rapper Jayquan McKenley was gunned down in Brooklyn. Mayor Adams has called for drill rap to be banned from social media — though his son is a fan.

Lil Mabu’s lavish life is a far cry from the gritty violence and crime he raps about.

“Can’t say no to the poles and I’m gon’ beat him down with a bat I put an opp in a wheelchair, give me like an hour, I’m leavin’ him flat,” he said in one recent new song called “No Snitching.” The line appears to be a reference to attacking police with a baseball bat. In an accompanying video, Mabu and a friend act out robbing a jewelry store. The video has 6.6 million views on YouTube.

“I call your b—h a wide receiver, she get open easy,” Mabu rapped in a misogynistic tune called “Wicked Witch.”

In another video, Throw, Mabu and a friend get into a staged shootout while leaving Mannys Juice Bar and Grill in Williamsburg, which results in Mabu taking a bullet to the shoulder.

Lil Mabu currently has 1.9 million followers on TikTok, with another 387,000 on Instagram and 331,000 subscribers on YouTube. Several of his social media posts appear to have been filmed inside Collegiate. Others show him getting bemused local reaction to his beats in ritzy Southampton.

“Drill rap is like aggressive music, yeah. Basically kids expressing their feelings, but in their way. It’s the way they do it because they can’t talk to nobody else. Best way to get everything off your chest,” said Chalim Perry, a rapper who has collaborated with Mabu under the name Sha EK.

Perry said Mabu was a “good kid’ and “ready to work” but that his life of privilege was limiting.

“He don’t have street cred, but they just respect it because they know he has music talent,” Perry said.

Mabu’s father, Peter DeLuca, 71, who sometimes makes cameos in his son’s work, might have a bit more street cred.

He is a Manhattan funeral director, who in 2006 was accused by ex-wife Jane DeLuca of conniving with a pair of disgraced Brooklyn judges to cheat her out of millions during their divorce. He’s fought legal turf wars with fellow undertakers and once took a punch to the face after allegedly soliciting future business from a client’s 91-year-old mother.

He also has a rare NYC permit to carry a concealed gun.

Collegiate insiders have been less than amused by the gangland cosplay.

“If this was any other child who did not have a rap career … who said anything close to what this kid is saying they would be expelled and would never be heard from again” one annoyed parent of a recent alum told The Post. “Collegiate used to be Latin and Greek and Math Olympiads, and now it’s TikTok.”

Lil Mabu didn’t always embrace the thug life, earlier videos in his oeuvre, like “Miss Me” have a relaxed, Justin Bieber-esque aesthetic. Before his music career — when he was just Matthew DeLuca — he was known for more conscientious pursuits.

“My name is Matthew DeLuca. I go to the Collegiate School. I am in 9th grade, and my favorite thing about Kids Walk for MSK Kids is getting together with friends and family to support such a wonderful cause,” he said in a Facebook video promoting his work to help pediatric cancer research.

When he attended Middle School at Buckley — where tuition is $55,500 per year — DeLuca was a standout student, even earning the coveted “Headmaster’s Prize for Strength of Character.”

Matthew and Peter DeLuca did not respond to multiple requests for comment from The Post.