Mary Jeff (1873–1941) was a Scottish activist and politician who was involved in the Glasgow rent strike.

She moved to Govan in 1896, and lived there with her husband, printer Andrew Jeff, and their three sons.

They both had a key role in the Govan rent strike, Andrew as chair of the South Govan Tenants Committee, and Mary as part of the group of women who campaigned against eviction, and orchestrated the defence against bailiffs.

[3][1] She was a member of the Kinning Park Co-operative Women's Guild and the chairwoman of the Ladies section of the Govan War Memorial Committee.

[4][5][6] In later years, she moved to Milngavie, where she was a member of Milngavie Bowling Club and an active member of the Deacon's court of St Luke's Church of Scotland.