The Neogene upper Youshashan formation in Huatugou area, Southwestern Qaidam, is one of the most important uranium bearing rock series. Its uranium reservoir development and uranium mineralization are closely related to hydrogeological conditions. The basement and caprock are rich in uranium, which are transported to the basin with groundwater after weathering and denudation to provide uranium source. During the period of upper Youshashan formation, the tectonic pattern of high in Northwest and low in Southeast controlled the seepage direction of oxygen-bearing uranium groundwater; the hydrodynamic force of distributary channel in braided river delta plain was suitable for uranium deposit enrichment and mineralization, becoming potential uranium reservoir; at the end of Pliocene, oxygen-bearing uranium fluid infiltrated into the potential uranium reservoir of upper Youshashan formation and was reduced and finally mineralized.