The interoperability test between power supply equipment and electric vehicle plays an important role in the popularization and application of electric vehicles. The principle of control pilot circuit is introduced firstly , in paper, then based on new national standard and the new charging interoperability test specification, the interoperability testing device of A.C. charging spot and in-cable control and protection device (IC-CPD) is designed。The test purpose and evaluation of the interoperability test items are stated, and the test items are tested and analyzed. The test results show that the following problems exist in the interoperability test of the charging spot: (1) the voltage value of the detection point 1 exceeds the allowable range of 0.8V. (2) charging connection control timing does not meet the standard requirements. (3) when the charging spot is under abnormal condition, it can"t disconnect the AC power supply circuit within the specified time.