On December 6, Cadet Seth Whale, from the No.18 Squadron, Air Training Corps, was nearby when a person was critically stabbed in Hoon Hay.
Whilst others assisted the person to the ground, Whale grabbed a towel and applied direct pressure to the wound until ambulance staff arrived.
The teen had attended a one-day Red Cross Essential First Aid Course a week earlier.
Commandant of the Cadet Forces Commander Andrew Law said, while the course provided Cadet Whale with the knowledge, it was his courage and determination that empowered him to take action in a critical first aid situation.
"CDT Whale's efforts during this traumatic incident demonstrated well the values of the New Zealand Cadet Forces, and were a key component in saving a human life. He is a worthy recipient of a Commandant's Commendation."
Commander Law said it was the first time in his tenure as commandant a commendation had been awarded to an individual cadet.
"When it came across my desk as a proposal, immediately I think, looking at it, the actions of the individual were worthy of recognition.
"When confronted with a trauma situation, rather than backing away, he demonstrated the personal courage to step up and there could be no greater decision or choice made than what he has done."
The stabbing victim received multiple wounds and was taken to Christchurch Hospital in a serious condition.
The police said the parties involved are known to each other and a number of people are assisting with inquiries.
