Emergency services were alerted to the incident in Miller Rd, around 2pm today.
The altercation occurred near the entrance road to Dunedin Airport on the Taieri Plain.
The man, who is now confirmed to have been stabbed, was initially reported to be in a moderate condition.
However, his condition deteriorated while being transported to Dunedin Hospital and he arrived in a critical condition, a police spokeswoman said.
Police confirmed the man subsequently died from his injuries.
It is believed the parties involved were known to each other.
Police are in the early stages of an investigation.
"Police are speaking with those involved and working to piece together the exact circumstances of the incident," she said.
The scene will remain cordoned off while an examination takes place.
A resident said he believed the altercation was about the victim's dog.
"A couple of [people] were screaming and fighting about dogs, and then one ended up on the ground," he said.
Anyone with information is encouraged to contact police on 105, and quote event number P052247485.
