San Sebastián is a city in the Basque Country, Spain.
San Sebastián or San Sebastian may also refer to:
Mexico
- San Sebastián del Oeste, a town and municipality in Jalisco, Mexico
- San Sebastián, Etzatlán, a locality in Etzatlán municipality, Jalisco, Mexico
- San Sebastián Tlacotepec, Puebla
- San Sebastian, Sinaloa, a place in Sinaloa, Mexico
Elsewhere
- San Sebastián, Aragua, a city in Venezuela
- San Sebastián, Tierra del Fuego, a settlement in Tierra del Fuego, Argentina
- San Sebastián, Comayagua, a municipality in Honduras
- San Sebastian, Lempira, a municipality in Honduras
- San Sebastián, San Vicente, a municipality in El Salvador
- San Sebastián, Quito, an electoral parish of Quito, Ecuador
- San Sebastián District, Cusco, in Cusco Province, Peru
- San Sebastián (district), a district of San José canton in Costa Rica
- San Sebastian (band), a rock band from Hamilton, Ontario, Canada
- "San Sebastian (Revisited)", a song by Sonata Arctica from their 2001 album Silence
- "San Sebastian", a song by Alien Ant Farm from their 2006 album Up in the Attic
- Saint Sebastian, an early Christian saint and martyr
- San Sebastián, Toledo, one of the oldest churches of Toledo, Spain
- San Sebastian Church (Manila), a Neo-Gothic church in Manila, Philippines
- Clásica de San Sebastián, a bicycle race
- San Sebastian College – Recoletos, an institution for higher learning in Manila, Philippines
- Siege of San Sebastián, a siege during the Peninsular War in 1813
- San Sebastián, a ship commanded by Francisco de Cortés Hojea on a 1557 expedition to explore Patagonia
- San Sebastian (horse), a British Thoroughbred racehorse