The incident, at a work premises in Carr Wood Road, Castleford, was reported shortly before 6.30am on Monday (November 20).
Emergency services rushed to the scene where the man was brought out from under the vehicle as paramedics commenced CPR.
But the casualty was pronounced dead a short time later. His family have been informed.
A spokesperson for West Yorkshire Police said: “The incident is being treated as an industrial accident and officers are liaising with the Health and Safety Executive.”
A scene has been put in place while enquiries are carried out into the circumstances. The coroner’s office has been informed.