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The Aghdarband is the only pre-Jurassic basement of the Kopet-Dagh basin exposed in NE Iran. The ophiolithic and igneous rocks of the Kopet-Dagh are exposed in the southwestern part of the study area. This complex divided to three rock units. First unit is ophiolithe melange that contains metaharzburgite, serpentinite and metagabro that are metamorphosed and alterated. Second unit is acid tuffs that forms in the different location at the edge of continental margin (magmatic arc). Third unit is a flysch type metamorphosed sediments that contains sequence of thin bedded shale and sandstone. These rock units are affected by three stage of faulting. First fault series are the thrust faults with northeast dipping. These faults are covered by the Kashafrud Formation (Lower Jurassic). Therefore, they were active during the pre-Jurassic time. In the other words, the subduction in the southern edge of Turan plate produced accretionary prism in trench and these faults were activated during this period. The end of subduction and collision of Iran and Turan plates in latest Triassic time and during Cimmerian Orogeny caused that this complex overriding on the Iran plate margin. Then, erosion of suture complex, including ophiolithic rocks, resulted the deposition of mollase detritic sediments at the base of Kashafrud Formation. Second stage of faulting is related to Paleogene activity where the Kopet-Dagh basin closed. These faults are also dipping toward northeast and displaced all of the sedimentary rock units of the Kopet-Dagh basin. This activity is related to Alpine Orogeny that contemporary closed oceanic basin of Neotethys in the Zagros basin as well as closure of epicontinental sea in the Kopet-Dagh region in the north of Alborz and south of Turan plate. Latest important tectonic activity took place about 5 million years ago after collision of Indian and Asian plates. This collision caused oblique compression and activation of oblique-slip or strike-slip faulting in the study area that is still active today. As a result of these activity, a thin-skinned fold-thrust belt is formed that can be seen in the Aghdarband area.