São Martinho (Portuguese for "Saint Martin") may refer to the following places:
Places In Angola São Martinho dos Tigres
In Brazil São Martinho, Rio Grande do Sul São Martinho, Santa Catarina
In Portugal São Martinho das Amoreiras, a parish in the municipality of Odemira São Martinho do Porto, a parish in the municipality of Alcobaça São Martinho de Angueira, a parish in the municipality of Miranda do Douro São Martinho (Alcácer do Sal), a parish in the municipality of Alcácer do Sal São Martinho (Covilhã), a parish in the municipality of Covilhã São Martinho (Seia), a parish in the municipality of Seia São Martinho (Sintra), a parish in the municipality of Sintra São Martinho (Funchal), a parish in the municipality of Funchal, Madeira São Martinho River, a river that is a tributary of the Sado River in Portugal
Other São Martinho, Portuguese Navy galleon São Martinho, one of the world's largest sugarcane processing operations