Mayu Ishikawa (石川 真佑, Ishikawa Mayu, born 14 May 2000) is a Japanese professional volleyball player from Okazaki City, Aichi, Prefecture. She's a member of the Japan Women's National Volleyball Team, as one of its outside hitters. She competed at the 2020 Summer Olympics, in Women's volleyball.
She currently plays for the club Azzurra Volley Firenze. She used to be the captain of Japan U-18 and U-20 national volleyball team.
Ishikawa has one older sister and one older brother, Yūki Ishikawa, who is the team captain of Japan men's national volleyball team. She was motivated by her siblings to start playing volleyball and her brother would always give good advice about spiking when she was in high school.