Abstract: The corrosion behavior of SPCC steel in salt spray corrosion environment was studied by cyclic salt spray corrosion test and numerical simulation. Based on the electrochemical test platform under thin liquid film, the corrosion numerical model of SPCC steel considering the influence of phase structure distribution and corrosion products was constructed. The results show that with the increase of corrosion time, the electrolyte potential gradually shifted from 0.59 V to 0.56 V, and the thermodynamic stability increased. The electrolyte current density decreased from 1.67 A/m² to 1.57 A/m². The corrosion depth and corrosion mass loss data calculated by the corrosion model were in good agreement with the experimental results.