The NW-trending Datca Graben, E-W trending Resadiye Horst, Gokova and Hisaronii Grabens are the most important morphologic and structural units of the Southwest Anatolia on which, tectonic evolution was controlled by NW-SE, NE-SW and E-W trending faults. The Datca Graben has been started to develop as a half graben on the Lycean Nappes of the central part of the Repdiye Peninsula under the control of NW-trending southern marginal fault during early Pliocene. Lagoonal-fluvial environment connected with shallow marine has evolved its evolution as a graben till late Pliocene (late Piacenzian). E-W trending Gokova Graben and Hisaronu Graben, started to develop under the effect of N-S directed extension, ends the development of the Datca Graben. The Gokova Graben is about 140 km long and enlarges from about 5 km to 30 km westward, and active Yali and Nisyros volcanic centers are located at the western tip of the peninsula. E-W trending southern marginal faults of this graben and northern marginal faults of the Hisaronu Graben cut the late Pliocene deposits of Datca Graben, forming Resadiye Horst between these two grabens. This is an important evidence for the development of Gokova and Hisaronu Grabens starting from early Quaternary.