Koki Ishii is a 32-year-old professional football player from JPN. He currently plays for AC Nagano Parceiro, wearing the number 16 shirt. He plays primarily as a Defender. He stands at 172cm tall and weighs 67kg.

Throughout the Japanese J3 League 2025, Koki Ishii featured in 22 matches, averaging 0.8 tackles, 0.6 interceptions, and 2.5 clearances per game, while blocking 0.1 shots per game.