The Greek mythographer and logographer Pherecydes of Leros (c. 450s BC) came from the island of Leros (and wrote the island's history, in a lost work) but spent the greater part of his working life at Athens, and so he was also called Pherecydes of Athens (Suidas considered them separate.)

His great treatises, a history of Leros, an essay On Iphigeneia, On the Festivals of Dionysus are all lost, but numerous fragments of his genealogies of the gods and heroes, originally in ten books, written in the Ionian dialect to glorify the ancestors in the heroic age of his 5th century patrons, have been preserved. He modified the legends, not with a view to rationalizing them, but rather to adjust them to popular beliefs.

He cannot, therefore, be classed with the later mythographer Hecataeus, whose Genealogiai ("Genealogies") were more skeptical and critical.

Pherecydes of Leros should not be confused with Pherecydes of Syros, the mid-6th century philosopher, one of the Seven Sages of Greece, reputed to have been the teacher of Pythagoras.