Based on the uniaxial tensile tests of 135 accelerated corrosion steel bars from 45 concrete specimens, quantitative relationships between uniform and non-uniform corrosion characteristic parameters of reinforcement bars and the mechanical and deformation parameters were established. Then the stress-strain model of corroded steel bars based on the above characteristic parameters was proposed. The results show that the correlations between the mechanical/deformation property parameters and the corrosion characteristic parameters of corroded steel bars are relatively high. The above mechanical/deformation property parameters of corroded steel bars decrease linearly with increase of the mass loss ratio, the maximum cross-sectional loss ratio and the relative maximum corrosion depth, while increase with the relative minimum residual cross-sectional area and the area pitting factor. Moreover, the yielding platform of the corroded steel bars deteriorates obviously with increase of degree of corrosion. When the mass loss ratio, the maximum cross-sectional loss ratio and the relative maximum corrosion depth is greater than 20%, 60% and 40%, respectively, or the relative minimum residual cross-sectional area and the area pitting factor is less than 40% and 60%, respectively, the yielding platform of corroded steel bars almost disappears. Both uniform and non-uniform corrosion characteristic parameters are suitable to describe the stress-strain curves of steel bars with slight corrosion, while the non-uniform corrosion characteristic parameters are more suitable for steel bars with severe corrosion.