Abstract: Several mineralizations occurring along the Simav Graben were formed in associations ith two principal tectono- magma tic periods dominated in the geotectonical development of the Western Anatolia. The dextral strike-slip Simav Fault trending WNW-ESE wasformed by the compressive tectonic regime prevailed in the paleo-tectonic period. Vein-type Pb-Zn-Cu mineralizations which areobserved in the region were deposited within the fractures sub-parallel to the Simav Fault, possibly associated with mafic dykes ofthe plutons in this period. The neo-tecionic period started in the region as the compressive tectonic regime changed to extensionalregime in the very beginning of Pliocene. Simav Graben was formed due to the activation of the lateral component of the Simav Faultby N-S extension. Transfer faults trending N-Scut the main graben fault during the later stages of the graben development. Epithern%almineralizations occurred along the graben were formed along such transfer faults. N-S trending faults in the region also form deposition sites for the epithermal mineralizations overprinting the base-metal veins formed previously. The present-day sinter precipitation at Ilıcalar (Gediz) and hot-springs in the vicinity of Simav along the graben are the recent equivalents of this epithermal activity. The epithermal mineralizations are associated with the porphyry dykes in the late stage of the granitoids.