The Amapá Railway is a former rail line built by Bethlehem Steel to exploit the manganese deposits in the territory of Amapá (now a state), Brazil. It is , the only railway in the country to use this gauge aside from Lines 4-6 of the São Paulo Metro. The line was also in use for passenger transport.
The line was about , spanning from mines near Serra do Navio to the port city of Santana. The rail line stopped transporting ore in 2014, and as of 2020, remains derelict.