Castanheira de Pera is a municipality located in the district of Leiria within the Central Region of Portugal. It is situated in the historical province of Beira Litoral.
The municipality covers an area of 66.77 km² and had a recorded population of 3,191 as of 2011. While it is sometimes erroneously written with an accent as Castanheira de Pêra, the standard spelling remains without the diacritic.