FAH may refer to:
- Folding@home, a powerful distributed computing project performing disease-relevant protein folding
- The FAH gene, fumarylacetoacetate hydrolase (fumarylacetoacetase)
- First Affiliated Hospital of Xinjiang Medical University
- Federation of American Hospitals
- The Honduran Air Force (Spanish: Fuerza Aérea Hondureña or FAH)