Joseph Barclay Pentland (17 January 1797; 12 July 1873) was an Irish geographer, natural scientist, and traveller. Born in Ballybofey (County Donegal, Ireland), Pentland was educated at Armagh. He also studied in Paris, and worked with Georges Cuvier.
With Woodbine Parish, Pentland surveyed a large part of the Bolivian Andes between 1826 and 1827. He published his Report on Bolivia in 1827. From 1836 to 1839, he served as British consul-general in Bolivia. He corresponded with Charles Darwin and William Buckland.
Pentland died 12 July 1873, and is buried in Brompton Cemetery, London.