West Kunlun is an important pegmatite−type Li−Be metallogenic belt in China. In recent years, a great breakthrough in prospecting has been made in Dahongliutan area, and a large mineral resource base has been formed. In this paper, detailed researches on petrography, geochronology and geochemistry of the spodumene granite pegmatites in Dahongliutandong, West Kunlun, can provide a new basis for the study of pegmatite−type lithium mineralization in this area. By using LA−ICP−MS zircon U−Pb dating, the ages of spodumene−bearing albite pegmatite and spodumene−bearing tourmaline granite pegmatite in the Dahongliutandong are 205.2±1.4Ma and 205.0±2.6Ma, respectively, in the Late Triassic. Geochemical study shows that spodumene−bearing granite pegmatites in the Dahongliutandong is characterized by high Si, rich Al, Na, calc−alkali, high differentiation and low K, Fe, Mg, Ca and Ti, and belongs to strongly peraluminous granite pegmatite. The pegmatites are obviously rich in elements such as Rb, U, Nb, Ta, Pb, P, Hf, but depleting in elements such as Ba, Th, La, Ce, Pr, Sr, Nd, Sm and Ti. The total amount of rare earth is low, with ∑REE of 0.56×10−6
, weak−medium negative Eu anomaly and δEu of 0.30～0.89. The pegmatites in the Dahongliutandong have low and negative εHf(t) values (–4.6～0) and the old two−stage Hf model age TDM2
(1497～1208 Ma), which indicates that their source rocks are from partial melting of ancient crustal materials. Based on the chronological data and the evolution characteristics of regional geological structure in West Kunlun, it is considered that pegmatite deposits in Dahongliutan area were formed in the background of post-collision between South Kunlun terrane and Tianshuihai terrane.