The smash happened on the Roguery Road in Toomebridge this morning, Wednesday, November 8.
The man was the passenger in a Rover car that was involved in a collision with a lorry at around 7 am on the Roguery Road.
The male driver of the car, also aged in his 30’s, has been taken to hospital where his condition is described as critical.
The driver of the lorry was not injured as a result of the collision.
Inspector Trevor Atkinson is appealing for anyone who was travelling on the Roguery Road this morning and who witnessed the collision to contact local officers in Ballymena or the Collision Investigation Unit on 101 quoting reference 167 08/11/17.