Abstract: The petrological results of the the calcalkaline volcanics which have covered large areas in Uşak areafrom the Middle Miocene to Upper Pliocene were given. These results were compared with the other volcanics of theAegean region, and the origin of the volcanics were interpreted according to plate tectonics. The first volcanic accumulationstarted in the Middle Miocene as rhyolitic and rhyodacitic tuffs and lavas. During the Upper Miocene, rhyodacitic,trachyadesitic and aiidesitic lavas, tuffs and agglomerates generated. Andesitic products developed in the Lower-Middle Pliocene, The characteristic rocks of the last volcanic period are the Upper Pliocene aged basaltic-andesites.There are some quiet epochs between these four volcanic periods. All the calcalkaline Uşak volcanics probably generated from a paleo-subduction zone which had occurred when the African plate met the Aegean plate in the "LowerEocene. Some data of the todays subduction zone of the Aegean Sea at the south of Crete Island which accordingto some authors probably had started in the Middle Miocene and it gave its first calcalkaline volcanism products 2,7million years ago and its volcanic activity continued to recent time were presented in order to define this paleo-subduction zone. Furthermore, some brief information about all the volcanics of the Western Anatolia and the AegeanSea were given to compare them to the Uşak volcanics.