Reinforced concrete is a material with high reliability and long life. In order to make accurate life prediction based on the geological environment of western saline soil, a composite solution composed of sodium chloride and magnesium sulfate is set to prepare reinforced concrete specimens with different water-to-binder ratios, and the specimens are placed in the solution for long-term immersion. The SEM, EDS and other tests are carried out for microscopic analysis to explore the corrosion law of reinforced concrete under multi-factor corrosion. Taking the relative corrosion current density as the degradation data and modeling, the Gamma stochastic process model is established based on the measured partial life data and then the remaining life is predicted. The results show that the corrosion resistance of reinforced concrete increases with the decrease of concrete water-binder ratio. The Gamma stochastic process can effectively describe the corrosion trajectory of steel bars in concrete, and it is feasible to predict the remaining life of reinforced concrete.