Craigieburn Police are investigating a sexual assault at a shopping centre on Main Street, Craigieburn.
Investigators have been told a woman, 31, was shopping when a man approached her and touched her inappropriately at 1.30pm on March 16.
The man then left the shopping centre.He is described as Caucasian in appearance, in his 50s, with grey hair.
He was wearing reading glasses, a cream top, brown pants and dark runners.
Investigators have released an image and CCTV footage of a man police believe may be able to assist with their enquiries.
Police urge anyone who recognises the man or who witnessed the incident to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au.