A man has been charged with sexual touching a teenage girl a train station, and approaching a woman on a Newcastle bound train.

About 11am, a 17-year-old girl was exiting a train at Central Railway Station when the 26-year-old allegedly sexually touched her.

The girl managed to get away from the man and reported the matter to railway staff, who contacted police.

The man boarded another train, which was bound for Newcastle and allegedly approached a 21-year-old woman about 11.20am, making her feel uncomfortable.

She moved away to an adjoining carriage before the man exited the train at Epping Railway Station.

About midday – in a third incident – a 17-year-old girl was exiting a restroom at Macquarie University Metro Railway Station, when the man is alleged to have pushed her back into the restroom.

The girl managed to push the man away and reported the matter to police.

About 12.30pm, another 17-year-old girl was exiting the same bathroom when the man allegedly dragged her back into the toilets.

The girl managed to get away and contacted police, who attended the scene a short time later.

Officers arrested the man on the platform of Macquarie University Metro Station and took him to Ryde Police Station.

The 26-year-old Koonawarra man was charged with sexually touch another person without consent (x 3), stalk/intimidate intend fear physical etc harm (personal), resist or hinder police officer in the execution of duty and goods in personal custody suspected being stolen.

He was refused bail to appear before Hornsby Local Court on Monday.

Inquiries are continuing.