Philostorgius (; 368 – c. 439 AD) was an Anomoean Church historian of the 4th and 5th centuries.

Very little information about his life is available. He was born in Borissus, Cappadocia to Eulampia and Carterius, and lived in Constantinople from the age of twenty. He is said to have come from an Arian family, and in Constantinople soon attached himself to Eunomius of Cyzicus,