The eddy current sensor is a key component of the eddy current testing (ECT) system that directly affects defect inspection. In this study, the detection performance of sensor was analyzed by ANSYS simulation and experimental verification. For further research, the influence of cylindrical coil sensor and rectangular coil sensor on the detection sensitivity of the groove defect in the placement mode and scanning direction were analyzed. The results show that the cylindrical coil sensor got similar results when using two scanning methods.