Mayu Iwatani (?? ??, Iwatani Mayu, ring name: ?? ??) (born February 19, 1993) is a Japanese professional wrestler currently signed to the World Wonder Ring Stardom promotion.
Since making her debut in January 2011, she became a one-time World of Stardom Champion, two-time Wonder of Stardom Champion, one-time High Speed Champion, one-time Goddess of Stardom Champion, and a four-time Artist of Stardom Champion, while also having won the Cinderella Tournament back to back in 2015 and 2016, and the 2018 5*Grand Prix.
She also makes appearances for Stardom's American partner Ring of Honor (ROH), where she is a former one-time Women of Honor World Champion .
Dave Meltzer of the Wrestling Observer Newsletter has called Iwatani and fellow Japanese workers Io Shirai and Kairi Hojo "three of the best wrestlers in the world".