A baby has been allegedly punched in the face in a bizarre attack at Sydney’s Central station today.

Police have charged a 28-year-old man with assault occasioning bodily harm after he allegedly approached the baby girl as she sat in her pram on Eddy Avenue and punched her in the face.

Police allege the man punched the 16-month old girl in the face before fleeing the scene.

As the man ran from the Eddy Avenue station entrance, the baby's father gave chase.

Police found the alleged offender on nearby Pitt Street. (9NEWS)

The father repeatedly yelled at the alleged offender to stop and called on witnesses to call the police.

Police allege they found the man in a nearby building on Pitt Street.

Officers speak with the couple. (9NEWS)

Despite being punched in the face, the baby only suffered a small cut.