Lil Xan has been hit with assault and battery charges months after cops say he got physical with a fan during a show in Boston ... and video appears to show him swinging at and kicking the concertgoer.

Law enforcement tells TMZ ... the rapper has been charged with two felony counts of assault and battery over the incident -- one count for the microphone he allegedly swung from the stage, the other for allegedly kicking the man in the head.

As we previously reported, Boston police were on the hunt for LX after the incident -- which happened in November at the Royale Boston nightclub -- as the "Betrayed" artist allegedly took off after witnesses say he spiked his mic and kicked the person in the crowd in the face.

At the time, we were told the attack was unprovoked ... but footage from the scene does seem to show the concertgoer flipping Lil Xan off at one point during the face-off. Other video appears to show Xan getting body-slammed onstage shortly after the alleged assault.

LX was hoping for a fresh start in 2025 ... earlier telling us he's now 3 years sober and planning to "never again" find himself in a similar situation.

So, despite his positive outlook, this drama is far from over.