Both vehicles caught fire following the collision.
The Stuart Highway in the state’s far north will remain closed for up to a week after the road surface was left badly damaged by the crash and subsequent fire.
The driver of the ute – a 23-year-old man from the ACT – and a passenger in the truck – a 57-year-old woman from Para Vista in South Australia – died at the scene.
The truck driver, a 49-year-old man also from Para Vista, was airlifted to the Royal Adelaide Hospital in a critical condition.
Police crash Investigators flew to the scene from Adelaide to investigate the crash.
The two deaths brings the number of lives lost on South Australian roads so far this year to 20, compared with 17 the previous year.
North-bound traffic on the Stuart Highway is being diverted at Pimba and vehicles travelling south towards Adelaide are being diverted at Coober Pedy.
This content first appear on 9news