Abstract: The results of the petropraphic and petrochemical investigation of the Middle-Upper Miocene agedigneous rocks which have covered large areas in Bodrum peninsula in Southeast Anatolia were presented, and theirregional distribution were investigated and their genetic implications according to plate tectonics were discussed. Inthe investigated area, the magmatism has started as mon zonitic plutons in the Middle Miocene at different locationsAfter the monzonitic plutons, which have hybrid magma tic origin and probably have calc-alkaline character, a violent volcanism affected the investigated area at the of the Middle Miocene, and widespread tuff-agglomerate depositsand calc-alkaline volcanic rocks such as andesite-dacite rhyodacite-rhyolite were formed- The calc-alkaline magmawhich have been originated by the anatexis of the continental crust and which have given those high potassiccalc-alkaline first stage volcanics have started to blend with alkaline primary magma of the mantle. The first stagevolcanism has ended with shoshonotic lavas of latitic and trachyandesitic composition. The second volcanic stagehas started during Upper Miocene. It had shoshonotic features at the beginning and had continued to form shoshonotic basaltic lavas- The primary magma which entirely had originated from mantle had been active in the latterstage. Totally alkaline trachybasalt-trachyte-comenditic trachyte and the alkaline rhyolite (comendite) which was thelast product of the alkaline series had formed as dykes. We conclude that the volcanicsm had originated as theproduct of the continental rifting because of the tension regime which had been dominant in Western Anatolia.