Fidelis may refer to:
- Fidelis (Bishop of Mérida), (550–560fl. 550–560)
- Fidelis of Como (died c. 304), Italian soldier-saint
- Fidelis of Sigmaringen (1577–1622), Capuchin friar martyred in the Counter-Reformation at Seewis im Prättigau, Switzerland
- Fidelis Books, an imprint of B&H Publishing Group
- Fidelis Security Systems, a computer security company
- Fideliscare, a New York HMO
- Fidelis Education, a technology company that provides an end-to-end solution for the military-to-civilian career transition
- Philipe Fidélis dos Santos, Brazilian footballer currently playing for C.S. Marítimo.