The Special Forces team were ambushed by a group of ISIS fighters when the Alsatian attacked two jihadis.
The furry fighter escaped the battle unhurt and has been hailed a hero by troops after saving the British team’s lives.
The brave pooch is thought to have been trained by the US Army.
The military operation took place last month on the Kurdish border. It is believed that the SAS soldiers were returning from a 10 day training programme for Peshmerga fighters. The pup was travelling with the group of British soldiers in a convoy of four vehicles.
The unsuspecting troops were caught unawares when they were trapped by a group of jihadis. The convoy was hit by a homemade bomb as around 50 ISIS fighters attacked. Leaving their vehicles to take cover, the SAS were split up between three areas.
When the British forces attempted to move out, jihadis attacked them from behind.
A US soldier travelling with the convoy let the heroic pup off the leash. The angry dog ran snarling towards the enemy fighters. The first jihadi was bitten on the neck and face. The dog slashed at the second fighter’s arm and leg.
The two ISIS fighters bravely ran away in terror after being savaged by the Alsatian.
A source told the Daily Star Sunday: "Military dogs sometimes accompany the SAS on operations. They are often used in strike operations and may well enter a building before any troops.
"The Alsatian was with the team in a training role but when the troops came under fire it was desperate to get involved.
"It could sense the tension and had an overpowering urge to protect it’s handler and the other troops.
"When the dog was unleashed it went after the greatest threat without consideration for its own safety ‐ this is what they are trained to do.
"A snarling Alsatian running at you is very frightening and probably not something the jihadis had encountered. The dog did its job and returned to its handler with its tail wagging."
US air support meant that the stranded SAS troops could get to safety.
It is thought that this is the first time that an attack dog has been used to directly save soldiers’ lives in Iraq and Afghanistan.