The accuracy of traditional shear strength models for corroded reinforced concrete (RC)beam are far from satisfactory, since these models generally belong to the empirical methods which are lack of theoretical basis and do not take into account the various influential factors comprehensively. Hence, a shear strength model of corroded RC beam which takes into account the influences of corrosion on key factors including the critical diagonal crack angle, the effective shear cross-sectional area, the reinforcement ratio and the stirrup ratio was established based on the modified compression field theory (MCFT). The accuracy of the proposed model was validated by comparing with 85 sets of experimental data and several existing models. Analysis results show that the proposed model is of good accuracy and small discreteness.