Lance Corporal Todd John Chidgey has been named as the Australian special forces soldier who died in a non-combat-related incident in Afghanistan.

The 29-year-old was found by colleagues in an administration building with a gunshot wound on Tuesday.

He was evacuated to a medical facility in Kabul where he underwent medical treatment but he died of his injuries.

Defence says Lance Corporal Chidgey joined the Army in 2006 and had been deployed on six tours to Afghanistan.

He was a member of the Australian Defence Force Headquarters in Kabul, serving as part of the Protective Security Detachment, providing protection for a senior Australian officer.

"Lance Corporal Chidgey's colleagues in the 2nd Commando Regiment have described him as a brilliant bloke to know and work with, who was loyal to the core and would do anything for his mates," Defence said in a statement.

"A consummate professional and a dedicated soldier, Lance Corporal Chidgey was one of the hardest-working members of the regiment who never sought recognition or reward."

Lance Corporal Chidgey, who was born in Gosford in New South Wales, is survived by his mother, father, brothers and partner, who are receiving support from Defence.

The ADF investigative service has begun an inquiry into his death.

"Defence requests that media respects the family's request for privacy and compassion," the statement said.

"Speculation about the circumstances surrounding Lance Corporal Chidgey's death is a cause of great distress for his family and friends."

The Sydney-based 2nd Commando Regiment soldier is the 42nd Australian to have died during the Afghanistan conflict and the 41st from the Australian Defence Force.

Posthumous Victoria Cross recipient Corporal Cameron Baird also served in 2nd Commando.