Casanova is a wanted man in NYC for an alleged brutal assault that left a woman with a busted jaw and stitches in her face ... TMZ has learned.

Law enforcement sources tell us ... a warrant was issued for the arrest of the "Set Trippin" rapper late Friday night. The alleged victim, Niya Rucker, claims she was attacked by Casanova and his crew at Good Stuff Diner around 4:40 AM last week.

We're told Casanova thought Rucker was filming him with her phone and became enraged, and an attempt to stop her and take her phone turned violent.

Law enforcement says Casanova and an accomplice assaulted Rucker -- leaving her with a possible fracture in her jaw and a facial laceration requiring 4 stitches -- and one of them put her in a sleeper hold.