Emergency services were called at about 9.30am to the Castlereagh Highway near Pearsons Lookout - about five kilometres south of the village of Capertee - following reports a NSW Rural Fire Service truck and a Ford Falcon had collided.

Police say the two male occupants of the Ford died at the scene. They have not yet been formally identified.

The four occupants of the truck were uninjured, according to police, and the male driver has been taken to hospital for mandatory testing.

Officers attached to Chifley Police District attended and have established a crime scene.

Police are appealing for anyone who witnessed the incident, or who has dashcam footage, to come forward and contact Crime Stoppers.

A report will be prepared for the information of the coroner.

Anyone with information about the incident is urged to contact Crime Stoppers on 1800 333 000 or https://nsw.crimestoppers.com.au.