A cyclist has been killed after he was allegedly doored and then hit by a truck in Melbourne's north.

Police believe the 25-year-old Italian national was riding with his partner on Sydney Road, Brunswick, about 4.10pm on Friday when a woman opened the door of a parked car and knocked him onto the road.

He was then hit by a passing truck, a Victoria Police spokeswoman said.

Paramedics rushed to treat the man but he died at the scene, an Ambulance Victoria spokeswoman said.

"Both the truck driver and the occupant of the parked car are assisting police with their inquiries," the police spokeswoman said.