Abstract: The impact of tectonic evolution and differential deformation on the distribution of oilfield water was discussed based on the analysis of tectonic kinematics and geometric characteristics of the western Qaidam Basin combined with the accumulation types and salinity distribution characteristics of oilfield water of the Neogene-Paleogene. The characteristics of differential structural deformation in the western Qaidam Basin are obvious. Controlled by the NW-SE oriented faults, the Yingxiongling Structural Belt features stratified deformation. The hydrochemical types, reservoir types, and salinity of oilfield water of the Neogene-Paleogene are controlled by differential tectonic deformation and multi-phase tectonic evolution. The early Himalayan Movement resulted in water storage structures and deep faults, which provided conditions for the convergence of oilfield water. The late Himalayan Movement promoted the further formation of reservoir space and the adjustment of oilfield water to high structures. The Yingxiongling and northwestern Qaidam structural belts where tectonic fractures develop in saline lacustrine sediments are the favorable areas for salinity enrichment, and the existence of gypsum-salt rock controls the vertical differential distribution of deep brine in the Yingxiongling Structural Belt.