Mary MacLean Hindmarsh (21 July 1921 – 10 April 2000) was an Australian botanist who worked at the New South Wales University of Technology in Ultimo as a professor of biology. A graduate of the University of New England in Armidale and the University of Sydney, she did a doctorate study on the effects of certain substances of cell division and root growth and research on a key to rainforest species south of the watershed of the Macleay River. Hindmarsh was a foundation council member of the Linnean Society of New South Wales from 1970 to 1974.