An NYPD cop was arrested early Friday for allegedly slapping his girlfriend, who was holding a 3-month-old infant, authorities said.

Officer Brayan Terrazas, 29 – who was off duty at the time of the incident – was cuffed at around 12:30 a.m. in Queens, cops said.

Terrazas was charged with endangering the welfare of a child, criminal mischief and harassment. He was suspended without pay, according to a police spokesman.

It’s unclear if the baby his girlfriend was holding was their child.

Terrazas also was collared in July 2012 for driving drunk after slamming his car into a concrete traffic median in Hunts Point. He pleaded guilty to driving while impaired.