Police suspect two homes were involved a gunfight on a south-west Sydney street overnight.

Three men inside a house on Francis Street escaped injury when several shots were fired into the front bedroom window and front fence at 7:50pm (AEST) yesterday.

Police say one of the men fired back at the house across the road within a minute.

Inspector Jason Donald says the first home has shattered windows, while the second home has a bullet hole in the roof.

"We're speaking to the occupants of those homes and witnesses in the area," he said.

"We don't know at this stage any more information that gives us a clear picture of what's happened.

"We don't want to speculate till we get firm facts but at this stage, we're still very much trying to get to the bottom of it, find a motivation."

There was a string of drive-by shootings on nearby Sackville Street in Fairfield late last year but Inspector Donald says Francis Street is not a regular trouble spot.

"These types of shootings have occurred out here but I'm not aware of anything in that particular street," he said.

Police are continuing their investigations today. Anyone with information about the shooting is urged to call Crime Stoppers on 1800 333 000.