A teenage boy was allegedly sexually assaulted while getting off a peak-hour train at Footscray station.

Police say the 17-year-old boy was getting off the train at Footscray Railway Station when he was sexually assaulted by the man.

The incident occurred about 5.20pm on Wednesday, February 22.

The offender then boarded a Sunbury bound train, getting off at Albion Railway Station.

Police are seeking this man captured on CCTV at Footscray station..

Police are seeking this man captured on CCTV at Footscray station.

The man is perceived to be of Caucasian appearance, 160-170cm tall with a stocky build and dark brown hair.

He was wearing a blue hooded jumper, satchel bag and jean shorts at the time of the alleged incident.

Police have released images of a man they are seeking to speak with.

Anyone who has information about the incident or the man’s identity is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential crime report at www.crimestoppersvic.com.au.