Tentoglou managed a best of 8.48 metres for his second gold, having also won in the Tokyo Games three years ago.
Jamaica's Wayne Pinnock took silver with 8.36m while Italy's Mattia Furlani claimed bronze, just 2cm adrift.
Greece's Miltiadis Tentoglou retains men's Olympic long jump gold
Greece's Miltiadis Tentoglou retained the men's Olympic long jump title in Paris on Tuesday.