Lysimachia (Greek: Λυσιμαχία) is a lake in Aetolia-Acarnania, western Greece.

Its area is 13.2 km2, its depth is around 9 m. It is fed by the small river Ermitsa, and by a canal that connects the lake with the larger Lake Trichonida to its east.

Its outflow is the river Dimikos, which drains into the river Acheloos.

The city of Agrinio lies 6 km to the northeast.

This Western Greece location article is a stub.