In order to solve the shortcoming of generally used measure method for Micro displacement,which is expensive and unable to automotive longtime watch,a sort of MDMS is gwen based on the corner reflector and microwave phase measurement.In the situation in which the direction of the micro displacement parallels to that of electromagnetic wave radiation,the basic MDMS is recommended.Otherwise the bend MDMS is recommended.The principle of MDMS is described.The example of channel calculation and circuit for transmitting measure result are also provided.The communication circuit transmits measurement to termination demanded.Finally the experiment results are given.