Diamantina may refer to:
- Australia
- Diamantina Bowen (1833-1893), grande dame of Queensland, Australia
- Diamantina Cocktail, 1976 album by Little River Band
- Diamantina National Park, Queensland, Australia
- Diamantina River, Queensland, Australia
- HMAS Diamantina, two ships in the Royal Australian Navy
- Shire of Diamantina, Local Government Area in Queensland, Australia
- The Diamantina Institute for Cancer, Immunology and Metabolic Medicine, institute of the University of Queensland, based at Princess Alexandra Hospital, Brisbane, Australia
- Brazil
- Chapada Diamantina, region of Bahia state in the Northeast of Brazil
- Diamantina, Minas Gerais, UNESCO World Heritage Site in Brazil
- João Paulo Diamantina, a Brazilian Film Director
- Elsewhere
- Diamantina Fracture Zone, Indian Ocean trench
- Diamantina Deep
- Latin binomial abbreviations for species
- A. diamantina
- B. diamantina
- T. diamantina