Noel Burke says the veterinarian at Crescent Falls Veterinary Hospital in Vernon, B.C. performed the amputation without first telling him his dog had cancer.
Burke said the procedure cost him $1,000, but he would have chosen to euthanize Coda, a St. Bernard-Black Lab-Rottweiler crossbreed.
Burke said he confronted the vet, who allegedly offered him $300.
"So I asked her, 'If you were in the wrong, why would you just offer me $300?'" Burke told CBC News.
"Why wouldn't you give me the full amount and then maybe put him down when it's time?"
The veterinarian refused CBC's requests for an interview.
Burke said he plans to file a complaint with the College of Veterinarians and take the veterinarian to court.