Two men have died after their truck veered onto the wrong side of the road and crashed down an embankment, on the Hume Highway at Gunning.

Police say early investigations suggest the B-Double truck carrying magazines was travelling south on the highway shortly after midnight on Tuesday, when it crossed the median strip into the north-bound lanes.

The truck then crashed through a guard rail and down an embankment.

The driver and his passenger died at the scene.

Police are investigating the cause of the crash and a crime scene has been established.

A report will be prepared for the Coroner.

Anyone with information about the crash should call Crime Stoppers on 1800 333 000 or go to www1.police.nsw.gov.au.