A semi-trailer carrying grain caught fire on the Kamilaroi Highway, 30km east of Narrabri, yesterday after an accident with a utility.
Emergency crews were called to the scene just before 2.00pm on Tuesday, the ABC reported.
A spokesperson for the New South Wales Ambulance Service said paramedics treated two drivers.
"A male aged about 28, suffered non-life threatening injuries and was transported by road ambulance to Tamworth Base Hospital in a stable condition," she said.
"The second patient, a male aged about 30, was treated for cuts and abrasions and was transported to Narrabri Public Hospital in a stable condition."
The Kamilaroi Highway was closed for nearly three hours while fire crews fought the blaze.
Superintendent Michael Brooks, with the Namoi-Gwydir Rural Fire Service, says five tankers responded to the accident.
"The first units found a large truck alight, semi-trailer, the cab and also the body which contained grain, I believe it was sorghum," he said.
"We responded tankers from around the area to give us the adequate water supply and that was required, with the assistance of the mines, who sent a 20,000-litre bulk water cart."