Ameinias the Phocian (Ancient Greek: Ἀμεινίας) (flourished 277/272 BC) was an ancient Greek pirate and mercenary leader in the service of king Antigonus II Gonatas of Macedon.
In his early career he had been a pirate captain, but in either 277 or 276 BC Antigonus Gonatas employed him to overcome the cruel tyrant of Cassandreia, Apollodorus, who had resisted a Macedonian siege for ten months.
Ameinias accordingly proceeded to gain the trust of the tyrant, pretending that his role was to reconcile Apollodorus to Antigonus and settle the dispute between them.
Meanwhile, Ameinias secretly prepared an army of two thousand men and a group of ten Aetolian pirates under the command of Melatas (or Melotas).
Observing that the walls of Cassandreia were thinly guarded, the pirates climbed to the parapet between the towers and fixed the ladders for the two thousand men, who immediately advanced and conquered the city.