An NYPD officer slugged his ex-wife so hard, he busted her lip, police said Monday after arresting the Finest on his second domestic assault rap.

Robert Castillo, 51, was charged with assault and criminal mischief after police arrested him around 1:30 p.m. Sunday at his ex-wife’s City Island home, according to a police spokesman.

The victim told police she asked Castillo, her ex-husband, to leave and he allegedly shoved her into a wall so hard that she smacked into a telephone, “causing the phone to become damaged and to break from the wall,” a criminal complaint says.

He then allegedly punched her in the face “with a closed fist, causing substantial pain, swelling, and a
bleeding laceration to informant’s lip,” the complaint continues.

The arrest happened in the area of City Island Avenue and Pilot Street, police said.

He was charged with assault and criminal mischief, cops said. It’s department policy to suspend arrested cops without pay.

Castillo was arrested in 2017 for violation of an order of protection, cops said. He also has an unknown number of sealed arrests, a police source said. The disposition of that case was unclear.