Considering the limitations of the current structure health monitoring techniques, a novel low-cost capacitive transducer (CT) using capacitance signals, which has the potential to provide accurate health assessment and damage prediction for reinforcement concrete structures, is firstly developed. Four major works including the development of the capacitive sensor, the optimization work of CT sensor design, the application of the CT in rebar size/depth/position and rebar corrosion tests using the developed CT are mainly introduced. Results have shown that the developed CT with innovative capacitance measuring method has great accuracy in predicting the rebar size and position inside a large structure, which is the foundation of the reinforcement corrosion detection. It can be concluded that the developed capacitive transducer is applicable in the condition tests of reinforced concrete structures and it paves the way for evaluation of the corrosion degree of the reinforced rebar.