Port and harbour facilities are exposed to severe environment so that deterioration and damages would be observed during in-service period. Corrosion of steel bars in concrete structures has a great influence on their structural performance and durability. Therefore，it is essential to evaluate the mechanical performance of those structures appropriately for the purpose of rational and efficient maintenance and repair work. At present，the degree of deterioration of concrete structures is judged based on visual observation to the surface appearance. In this case，tbe judgement is qualitative and subjective so that it is impossible to evaluate the structural performance accurately. Hence，in this study，the applicability of nondestructive testing methods to structural performance assessment evaluation was investigated in order to obtain quantitative and objective information regarding the deterioration in concrete structures. Reinforced concrete beam specimens subject to electrolytic corrosion were prepared，and the material deterioration of the specimens was analyzed and quantified. Through bending tests on the specimens，the relationship between material deterioration and structural performance was examined，and the nondestructive testing methods were applied to the deteriorated specimens. As a result，it was possible to evaluate the deterioration state inside the specimens by acoustic emission measurement. Furthermore，the degree of corrosion of steel bars in concrete could be estimated quantitatively by measuring the half cell potential and the polarization resistance based on electrochemistry.