Masaaki Yuasa (湯浅 政明, Yuasa Masaaki, born March 16, 1965) is a Japanese director, screenwriter, and animator affiliated with Science SARU, a Japanese animation studio which he co-founded with producer Eunyoung Choi in 2013. Yuasa previously served as president of Science SARU, but stepped down from this role in 2020. Recognized for his idiosyncratic art style and directorial voice, Yuasa began his career as an animator on the landmark television series Chibi Maruko-chan (1990–1992) and Crayon Shin-chan (1992–present), before moving into directing with the feature film Mind Game (2004) and developing a cult appeal following.