With Facebook “friends” like this, who needs enemies?

A reputed Bronx gang-banger who boasted online about his alleged criminal exploits had his “private” posts reviewed by the feds after one of his Facebook friends turned rat.

Melvin “Melly” Colon — who used the online alias “Mellymel Balla” — claimed his constitutional rights were violated when the feds searched his account.

But Manhattan federal Judge William Pauley III ruled any evidence gleaned from the account was done so legally, even though Colon “undoubtedly believed that his Facebook profile would not be shared with law enforcement.”

According to court papers, Colon’s posts included: “Im trying to see the man for like 600 grams” — which the feds say is a reference to crack cocaine — and “Wats ya body count n—a im triple digits!”

Colon, 20, also allegedly posted several photos of himself and others “making hand gestures commonly referred to as ‘gang signs.’ ”

Colon was busted last year on a slew of charges tied to his alleged leadership of the Courtlandt Avenue Crew.