Abstract: Donggou ophiolite occurs in Zamashi area along the eastern segment of northern Qilian orogenic belt. The ophiolite is mainly composed of pyroxene peridotite, gabbro and mafic volcanic rocks, making up a relatively complete ophiolite unit. Single-grain zircon LA-ICP-MS U-Pb isotopic dating of mafic volcanic rocks yielded a weighted average age of 499.3±6.2 Ma, which represents the ophiolite formation age, equivalent to Late Cambrian. According to geochemical studies, the ophiolite mafic volcanic rocks are of tholeiitic series, the chondrite-normalized REE patterns are nearly of flat-type; the (La/Yb)N ratios are between 0.97 and 1.26; the trace element distribution patterns basically show flat curves with the exception of a few large-ion lithophile elements (Ba, Rb, U, K); Nb, Ta, Zr, Hf have not experienced loss, suggesting geochemical characteristics of mid-ocean ridge basalt (N-MORB); in Zr-Zr/Y and Ti/100-Zr-3Y tectonic discrimination diagrams, all the samples fall into the MORB area formed in mid-ocean ridge. A comparative study of the region shows that the ophiolite and Yushigou as well as Cuancigou ophiolite jointly constitute the spreading ridge-type ocean ophiolite.