Police have released a facial composite of a man they believe could help with their enquiries.

Police said the victim was working at a store on Ararat Road on Saturday, May 21 about 1.30pm. 

The woman, 28, was making coffees when an unknown man took dishes to the dishwasher located behind the counter. 

Police allege the victim thanked the man, who then approached her and indecently assaulted her.

The woman did not say anything and continued with her duties, while the man returned to his seat. 

Police describe the man as aged in his mid to late 50s, with an olive complexion, slim build, large nose, brown eyes and balding on top with brown and grey hair.

At the time of the incident, he was wearing a navy polo fleece jumper and navy track suit pants. 

Police said the man was sitting with another man, who was described as being a similar age with white hair.

They urged anyone with information to call Crime Stoppers on 1800 333 000 or submit a confidential crime report to www.crimestoppersvic.com.au.