The incident took place inside and outside a flat on Craigielea Road on Sunday, April 7, shortly after 6.30pm.
Officers say they were called after a 34-year-old man sustained a serious head wound following a disturbance.
He was rushed to hospital for treatment before later being discharged.
Cops believe the man was assaulted whilst within a party and the fight then spilled into a common close and garden.
Currently, police say only two other men were involved in the incident.
They are both understood to be Scottish, with one being described as mid-30s, 5ft 10inch in height, had short dark hair, and was wearing an all-grey Adidas tracksuit and black trainers.
Now, officers are appealing for information on the disturbance.
Detective Sergeant Craig McGarry, Clydebank CID, said: “We believe that the man was assaulted whilst within the party and the fight then spilled into the common close and then garden.
“From our enquiries so far, there appear to be two other men involved who are both white Scottish. Only one description has been given and that is one man was mid-30s, 5ft10 in height, had short dark hair and was wearing an all grey Adidas tracksuit and black trainers.
“We know that there was a large number of people in the area, some of whom were at the party, so we’d appeal to them to come forward if they have not already been spoke to by police.”
