Haruna began coaching with teams of the Japan Ice Hockey Federation immediately following his retirement from playing in 2016. He served as the goaltending coach (often recorded as assistant coach) to the women's national team at the qualification tournament for the 2018 Winter Olympics, the 2017 Asian Winter Games, the 2017 IIHF World Championship Division IA, the 2018 Winter Olympics, the 2019 IIHF World Championship, and the 2021 IIHF World Championship; to the men's national team at the qualification tournament for the 2018 Winter Olympics, the 2018 IIHF World Championship Division IB, the 2019 IIHF World Championship Division IB, and the pre-qualification tournament for the 2022 Winter Olympics; and to the women's national under-18 team at the 2018 IIHF World U18 Championship Division IA and the 2019 IIHF World U18 Championship, in addition to coaching the three teams at various international friendly matches and tournaments.