About 11am on Sunday, emergency services were called to the Bruxner Highway, about 20km east of Tenterfield.

On arrival, they found one person dead after a motorbike with a side car left the road and crashed down an embankment.

A crime scene was set-up and part of the road has been closed as detectives and forensic police comb the scene.

Police were still at the scene on Sunday afternoon and investigations continue.

A report will now be prepared for the coroner.