Western Australian police say they've located a body believed to be that of a man who went missing off the Pilbara coast at the weekend.

The 27-year-old had been missing since Saturday, after he was thrown overboard in the Dampier Archipelago when his boat struck a mooring.

Police said the body was located in the search area and a report will be prepared for the coroner.

The man was travelling with a friend about 11pm on Saturday when they struck a mooring near West Lewis Island, throwing them overboard and sinking the boat.

One man swam to safety, where he was reunited with friends camping on the island before being taken to hospital.

Specialist police divers and a drone were flown to the region to help with the search, and the sunken boat was recovered from waters off Enderby Island on Monday afternoon.

Police said on Sunday they did not think the men were wearing life jackets.

The incident happened when the pair were running an errand from West Lewis Island to the Dampier boat ramp about 10.45pm on Saturday, and they hit the mooring on the way back out.