Maurine Stuart (3 March 1922 – 26 February 1990), a.k.a. Ma Roshi or Mother Roshi, was a Canadian Rinzai Zen rōshi who was one of the first female Zen masters to teach in the United States. She became president and spiritual director of the Cambridge Buddhist Association in 1979.
Stuart was granted her teaching title during an informal ceremony in 1982 held by her teacher Soen Nakagawa. Nakagawa, who had given Dharma transmission previously to five individuals (all male), granted Stuart the title in defiance of convention. While she had accepted the roshi title, she never declared to be a Dharma heir or lineage holder. The title was conferred upon her independent of her previous Zen practice and 1977 ordination as a Zen priest by Eido Tai Shimano.