In 2016, Ideguchi played for the Japan U-23 national team at 2016 AFC U-23 Championship. Japan won the champions and qualified for the 2016 Summer Olympics. At 2016 Summer Olympics, he played 2 matches as central midfielder. On June 7, 2017, he debuted for the Japan national team against Syria. He played 15 games and scored 2 goals for Japan until 2019.