Four male farm workers who died in a crash in northern Hawke's Bay had been drinking at a local hotel, police say.

The alarm was raised around 7.30am on Sunday by a passing motorist who saw a Mitsubishi Pajero over a bank on Waikare Road just off State Highway 2 near Putorino, 60 kilometres north of Napier.

The four men aged 47, 64, 42 and 48 all lived in the area and were working as farm hands, Senior Sergeant Sarah Stewart said.

Three of them were thrown from vehicle and it is not yet known if anyone was wearing seatbelts.

The men had been drinking at a local hotel and police believe alcohol was a factor in the crash. They are still trying to work out when the crash happened.

The driver lost control of the vehicle on a slight crest on an unsealed road. The car slid across the road, flipped, crashed through a fence and landed on its wheels in the paddock.

The men were dead when police and ambulance arrived.

Police want to talk to anyone who may have seen the crash or seen the blue-grey Mitsubishi Pajero wagon in the northern Hawke's Bay area in the previous 24 hours.