Police are hoping to identify a man following a series of bike thefts at a Clayton educational facility this month.

Investigators believe the unknown man entered the College Walk campus about 6.20pm on July 13, about 2.40pm on July 16 and about 9.50am on July 29.

Each time the man approached a bike rack and cut through a secured lock or chain before stealing a bike.

Investigators have released images of a man who they believe can assist with their enquiries.

The man is perceived to be Caucasian in appearance, aged in his 30s, with a medium build and dark hair.

He was wearing a bright red cap each time.

Anyone who recognises the man or with information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppervic.com.au