This article studies the formation cold damage problem in the water injection development of tight oil reservoirs in northern Shaanxi, evaluates the impact of increasing the temperature of reinjection water on the water flooding effect, studies the mechanism of hot water flooding, and explores the significance of using geothermal energy to increase the temperature of reinjection water. By utilizing reservoir rock cores, crude oil, and formation water samples taken from oilfield sites, and in accordance with relevant industry standards, the impact of hot water injection on the physical properties of crude oil, rock properties, and rock fluid interaction is studied through analysis and experimental systems such as fluid property testing, relative permeability testing of reservoir rock cores, and water driven oil experiment. The research results indicate that as the injection water temperature increases, the density and viscosity of crude oil can be reduced, and the flowability of crude oil can be improved; Lowering the water injection temperature can significantly reduce the permeability of rocks, proving the existence of cold damage to reservoir rocks. Increasing the reservoir temperature can significantly restore the permeability of rocks, and cold damage to rocks can also be partially restored; Raising the water injection temperature can improve the efficiency of water flooding, and with the synergistic effect of oil displacement agents, the effect is better. This article uses experimental methods to study the mechanism of hot water flooding in tight oil reservoirs in northern Shaanxi, providing a theoretical basis for the development of hot water injection in tight oil reservoirs and technical support for the development of new uses of geothermal energy in northern Shaanxi oil fields.