The Ahar area is located on an orogenic tectonic setting from magmatic and tectonic point of view. The young volcanic rocks, are composed of basalt, andesite, trachyte, and dacite in composition. The volcanic geochemically are calc-alkaline and show linear–like correlation in major oxide variation diagrams, which are revealed in main mineral phase fractionations. They also exhibited enrichment in Ba, U, La, Pb, and Sr and depleted in Cs, Nb, Ti, and Ce. The 143 Nd/ 144 Nd, 87 Sr/ 86 Sr, and Nd(i) values are changing from 0.704183-0.705077, from 0.512749-0.51286 , and 1.6-2.6, respectively. Fractional crystallization and contamination seem to have been important in the evolution of the volcanic rocks. Nd and Sr-isotope compositions fall in the field of oceanic island basalt (OIB) and extend along with the mantle array. Geochemical data suggested that the parental magma of the studied volcanic rocks were magma that originated from the enriched lithospheric mantle and asthenosphere. According to the regional geology and petrological data, these volcanic rocks have a post-collisional feature, and formed in an extensional tectonic settings. The geochemistry model of trace elements and isotope ratios in the samples reveals that all of them are derived from a mantle resource. They enriched and metasomatized extensively by continental crust via the subduction process with a crustal metamorphic materials in a continental collisional tectonic setting. These rocks are derived by a varying degrees of partial melts with a lithospheric mantle resource.