The man was shot in the chest on Monday afternoon at about 10.15am at Kaimai-Mamaku Forest Park. He was in a remote area about two hours from the carpark with no communication.
The Auckland Westpac Rescue Helicopter was sent to the remote spot after another hunter raised the alarm and a paramedic was winched down to help the man.
The shooting comes at the beginning of the Roar, which runs from late March through to April.
Meanwhile police are reminding hunters to stay safe because there is a significant increase in the number of hunting-related incidents and Search and Rescue operations at this time each year, with target misidentification being the biggest cause of fatalities.
Detective Senior Sergeant John Wilson urged those going hunting to follow the seven rules of firearms safety and said when a hunter was identifying deer they needed to make sure they look at the whole animal.
"If in any doubt don't shoot. If you pull the trigger you will have to live with the consequences forever," he said.
"Of these seven firearms safety rules, failing to identify your target is the most likely to see another hunter mistakenly shot," Wilson said.
The seven rules of firearms safety:
1. Treat every firearm as loaded 2. Always point firearms in a safe direction 3. Load a firearm only when ready to fire 4. Identify your target 5. Check your firing zone 6. Store firearms and ammunition safely 7. Avoid alcohol or drugs when handling firearms Source: NZ Police