Mithymna (Greek: Μήθυμνα, also sometimes spelled Methymna) is a town and former municipality on the island of Lesbos, North Aegean, Greece. Since the 2011 local government reform it is part of the municipality Lesbos, of which it is a municipal unit. An alternative, unofficial name for the town is Molyvos (Greek: Μόλυβος); that name dates back to the end of the Byzantine Era, but is still in common use today.