Fonseka is a Sri Lankan surname of Portuguese origin. Notable people with the surname include:
- Andrea Fonseka (born 1984), Malaysian actress, model, beauty pageant titleholder
- Anoma Fonseka (born 1957), Sri Lankan wife of Sarath Fonseka
- Damayanthi Fonseka (born 1960), Sri Lankan Actress
- Malini Fonseka (born 1947), Sri Lankan actress
- Samanalee Fonseka (born 1981), Sri Lankan actress and singer
- Sarath Fonseka (born 1950), Sri Lankan military leader and politician
- Senali Fonseka (born 1992), Sri Lankan actress