Abstract: The metamorphic rock succession between Kula-Ala§ehir region, Demirci-Gördes submassif, can be given, in ascending order,as follows; micaschists compraising gneiss levels and leuococratic metagranile bodies; gneiss, migmatites associated with granitesand acidic metavolcanites of the core series and garnet micaschists of the cover series. Also, metagabbro stock, approximentally Ikm in wide, and a number of metagabbro sills occur in the acidic metavolcanites.It was determined that the metagabbro stock represent some textural and mineralogical changes toward the core which were resulted from the highgrade metamorphism affected both the country rocks and metagabbros. These metaigneous rocks can be petrographically subdivided in three rock types from the margin to the core; garnet amphibolite, amphibolitic metagabbro and metagabbro. The metagabbros were completely converted to the garnet amphibolites at the marginal zone in which they were stronglyaffected by the metamorphism. In these zones were the rocks were strongly foliated parallel to those of the country rocks, the garnetamphibolites have a purely metamorphic mineralogy and texture. In the amphibolitic metagabbro zone, the primary igneous textureand mineralogy were partly preserved. In the inner parts of the stock, the metagbbros are remarkably free of metamorphic effectsand consist of "Plagioclase + Ortho I Clinopyroxene + Hornblende + Clinozoisite ± Garnet ± Biotite ± Sphene ± Opaquoxide". Anumber of metagabbro sills, up to 100 m in lenght, which were partly completely converted to garnet amphibolite occur in thecountry rocks around the metagabbro stock.At the nortlwr part of Alaşehir, these basic igneous rocks gabbroic in composition occuring in the core series of the MenderesMassif were contemporaneously subjected to highgrade metamorphism with the country rocks. It is obviously understood that, interms of the geological setting, structural features, mineralogical composition and textural evidence, the metagabbros, probablyPrecambrianJCambrian in age, which are exposed in Ala§ehir-Kula region have great similarities with the gabbros all over theMenderes Massif which are previously regarded to be Middle Mioce in age and post-metamorphic in character (According to thesenew evidences, it can be postulated that the gabbros which are exposed all over the Menderes Massif are of PrecambrianiCambrianin age and were subjected to high - grade metamorphism effected the Menderes Massif during the Middle Eocene time.