The Shuigou vanadium deposit occurs in the black rock series of Lower Cambrian Shuigoukou Formation in southern Qinling. The characteristics of major elements, trace elements, REE and oxygen isotopes of vanadium ore indicate that Shuigou vanadium deposit formed in the anoxic sedimentary environment in the intermediate zone between continental margin and deep-sea, the sediment come from the mixed zone between the submarine hydrothermal spring and the land-source area, biological activities have an important effect on the conglomeration and precipitation of the ore-forming materials. It is concluded that the vanadium deposit should be of biological and hydrothermal sedimentary origin.