Dercyllus the Historian was a 4th-century BCE author of a local history of Argos. No biographical details survive beyond this attribution. His obscurity is such that he is referenced primarily as a potential source used by later, more prominent historians.

His sole known work is the Argolica, a history of Argos. The text is lost, surviving only in a handful of fragments and later citations. Dercyllus represents the genre of local history, or horography, common in the Classical period.

His significance lies in his role as a source for Argive history, possibly utilized by later compilers like Diodorus Siculus. He serves as evidence for the breadth of historical writing beyond the major surviving authors.