In Greek mythology, Spercheus (also Sperchius, Spercheius, Spercheios, Sperkheios) was the name of and the god of a river in Thessaly.

According to Antoninus Liberalis (22) the nymphs of Mount Othrys were daughters of Spercheus by Deino, whether the same Deino elsewhere named as one of the Graeae or another is not said. Liberalis also says that King Dryops of Oeta was son of Spercheus by Polydora daughter of Danaus, the same Dryops who was father of Dryope.

In Homer's Iliad, Spercheus is father of Menesthius , one of Achilles' commanders, by Achilles' half-sister Polydora.

The river begins in the Eurytania prefecture in the Panaitoloko mountains and flows northeast from near Megalo Chorio and into Karpenisi and flows within GR-38 and through Agios Georgios Tymfistos south of the Tymfistos and into the modern prefecture of Fthiotis. The river flows into a plain in the west-central part and into south of Lamia. The river flows into an area which was dominated by swamp and wetlands which much of the land became used for farming and empties tinto the Malian Gulf .