Abstract: Eddy current method is a common technique to measure the displacement of carbon fiber reinforced composite (CFRP). CFRP often works on high level load, and the influence rule of load was studied with both theoretical and experimental methods in this research. The so called equivalent eddy current ring was used to develop the model aiming to simulate the measurement of CFRP displacement by eddy current method. In order to conduct experimental research, an experimental system was built. A kind of thin board, which is unidirectional CFRP, was taken as the specimens. The sensor calculation experiments were conducted for this specimen and the results were compared with numerical simulation results in detail. The validity of the theoretical model was proved. The influence rule of the load was analyzed.