The Hongliugou ophiolite melange is situated along the Altun fault, NW China. Two detailed profile sections across the melange belt are made. The petrochemical characters of igneous rocks show that there are two types of basalt in the ophiolite melange: MORB and OIB, with REE distribution patterns being flat-type and LREE-rich-type respectively. Combined with the Sm, Nd isotope study, we infer that meta basic rocks in the Hongliugou ophiolite melange were derived from different mantle resoures. The mantle peridotites in Hongliugou ophiolite melange, with low REE abundance, have two types of REE distribution patterns too. All the results above-mentioned indicate such an assemblage of MORB and OIB probably the mixed product of mantle plume and ocean crust.