The incident took place near Mount Anderson Station in Camballin, a small town in the state's Kimberley region.
Emergency services were notified of the crash at about 6.20 am local time on Thursday (2220 GMT on Wednesday).
Early indications suggested that two cattle-mustering helicopters collided shortly after taking off.
"Both helicopters only had one person on board. Sadly, both pilots - a 29-year-old man and a 30-year-old man - died as a result of injuries received during the crash," said the Western Australia Police Force.
According to police, the Australian Transport Safety Bureau also received notifications and would conduct a transport safety investigation into the incident.
-- BERNAMA
