Man allegedly punches officer 20 times

A 27-year-old man has been charged over a frenzied attack on a Sydney policeman who was punched in the head up to 20 times.

He's also accused of punching another policeman in the forehead.

The officers were attacked on Sydney's Oxford Street in Surry Hills in the early hours of Sunday, while responding to reports that a man was yelling obscenities at staff in a fast-food restaurant.

The first policeman has numerous cuts to his face and the second officer has swelling and bruising.

Other police arrived to arrest the man who's been charged with two counts of assault causing actual bodily harm against a police officer executing their duty and for behaving in an offensive manner.

He was refused bail to appear in Parramatta Local Court on Sunday.