Vlahos or Vlachos (Greek: Βλάχος [ˈvlaxo̞s]), feminine: Vlahou, is a Greek surname, meaning Vlach.
The surname Vlahos/Vlachos may refer to:
- Alexander Vlahos, Welsh actor, known for playing Mordred on Merlin
- Eros Vlahos, English actor, known from Game of Thrones
- Helen Vlachos, Greek journalist and newspaper editor in the 60's, daughter of Georgios
- Dionisios Vlachos, American Professor of chemical engineering
- Georgios Vlachos, Greek journalist, creator of Kathimerini, a daily newspaper in Greece
- Leesa Vlahos, Australian former politician
- Michalis Vlachos, Greek footballer
- Petro Vlahos, American engineer, bluescreen/special effects pioneer
- Terpsichori Chryssoulaki-Vlachou, Greek WWII resistance member
- Tony Vlachos, winner of Survivor: Cagayan
- Vangelis Vlachos, Greek footballer
- William Vlachos, American footballer
- Zachary Vlahos, American Olympic rower