The collision happened shortly after 1pm yesterday on the A629 Penistone Road and involved a white Fiat Ducato and a blue Renault Clio.
The male driver of the Clio suffered serious injuries and was taken by air ambulance to Leeds General Infirmary.
The driver of the Ducato suffered minor injuries.
Sergeant Steven Suggitt, of the Western Area Safer Roads and Neighbourhood Support Team at West Yorkshire Police, said: “As part of our enquiries in to this incident, we are keen to speak to anyone who either witnessed the collision or the manner of driving of either vehicle immediately prior to it.
“Anyone with information is please asked to call the Western Area Safer Roads and Neighbourhood Support Team via 101, quoting log 611 of 17 February.”