Izumo is a Hidden Leaf chuunin. He and his friend, Kotetsu, held their own unofficial first test at the beginning of the chuunin exam. They used genjutsu to switch the room numbers and trick the candidates for the exam. Izumo and Kotetsu later became the Fifth Hokage's assistants; the pair often ran errands for Tsunade.
Izumo was a member of the task force that Tsunade set out to capture Hidan and Kakuzu when they entered the Land of Fire in search of Uzumaki Naruto. Izumo was in a team with Asuma, Shikamaru, and Kotetsu. Izumo And his team met up with the two Akatsuki members and attempted to ambush Hidan and Kakuzu. Izumo, Kotetsu, and Shikamaru were forced to fight Kakuzu while Asuma took on Hidan. Izumo was able to stop Kakuzu for a moment when he coated the ground with his syrup capture field jutsu while Kotetsu attempted to attack Kakuzu. Kakuzu overpowered the three and forced them to watch Hidan kill Asuma.