Grant Duff
Grant Duff is a family name that may refer to:
- Arthur Cuninghame Grant Duff (1861–1948), British diplomat
- Evelyn Mountstuart Grant Duff (1863-1926), British diplomat
- Mountstuart Elphinstone Grant Duff (1829-1906), Scottish politician (including Governor of Madras) and author
- Shiela Grant Duff (1913–2004), British resistance fighter and author