Zinc may be extremely toxic when absorbed from a metallic foreign body retained in the stomach. The most common cause of zinc toxicosis in dogs appears associated with accidental ingestion of copper-coated zinc pennies minted after 1982. In a retrospective literature search, zinc toxicosis due to penny ingestion was reported in 5 dogs, 2 of which died postoperatively, and 1 was euthanatized due to severe multiorgan system failure. In this report, we describe 3 additional cases of zinc toxicosis due to penny ingestion that resulted in a fatal outcome. Two dogs died during the early postoperative period, and another dog was euthanatized 5 d postoperatively due to continued deterioration. These cases emphasize the potential of perioperative complications associated with zinc toxicosis due to penny ingestion and suggest the need for better treatment options to decrease postsurgical mortality associated with this disease entity.