Lil Nas X is now facing years in prison … because the L.A. County District Attorney has charged him with 4 felonies … including battery with injury on a police officer.

TMZ broke the story … the “Old Town Road” rapper was naked on Ventura Blvd. in the San Fernando Valley when cops were called. They say when they confronted him, he charged the officers … and presumably injured at least 3 of them — hence the 3 felony charges.

Nas was also hit with a felony charge of resisting an executive officer — i.e., a cop.

The rapper was held without bail over the weekend until he could appear before a judge, which happened Monday morning.

He’s set to be arraigned later today. So far, bail has not been set, but that should happen when he’s arraigned.

When cops arrested Nas … they thought he was high on drugs, so they took him to a hospital and later transferred him to jail.