In this paper, SHRIMP U-Pb zircon dating on the granite from the Serbulak iron deposit district in the sounthern maugin of Altay in Xinxiang shows that it was formed at 410±4 Ma (MSDW=0.88) equivalent to late Silurian or early Devonian. This age defined that the stratum intruded by the above pluton was formed at pre-Devonian more than 410 Ma, rather than previously considered middle-Devonian and the Serbulak skarn iron deposit was formed at the end of late Silurian or the beginning of early Devonian appreciably late than 410 Ma. Geochemically, the Serbulak granite is relatively riched in silica, alkaline, Th, U, La, Ce, Nd, Zr, Hf and markedly fractionated LREE , is predominantly depleted in Nb, Ta, Sr, P, Ti, weakly fractionated HREE and contains moderate Eu negative anomaly (δEu=0.35-0.47). All of the Na2O/ K2O ratios are around 1, indicating calc-alkaline to high K calc-alkaline series. The A/CNK ratios range from 1.07 to 1.14, indicating peraluminous granite. The apparent similarity of geochemical features on trace elements to the Mengku pluton (400 Ma-404 Ma) implies that the Serbulak pluton was formed in a continental arc and an active continental margin setting related to the subduction of plate where the femic rocks from the oceanic crust may melt and the components from crust may be trapped.