Tomasz Gladkowski, 39, and his seven-year-old son were at the main beach in Port Albert, Ont., on Sunday.
Police say Gladkowski went into the water to rescue his son, who was struggling with a powerful undertow at the mouth of the Nine Mile River.
Although the boy made it safely back to shore with another man's help, Gladkowski didn't make it back and was reported missing at 3:30 p.m. ET.
Two OPP marine vessels, the Canadian Coast Guard and a helicopter from the Joint Rescue Coordination Centre in Trenton were deployed to search for the missing man.
At 1:45 p.m. on Monday, the OPP's Underwater Search and Recovery Unit found Gladkowski's body about 150 meters from the shoreline.
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