In order to prevent the T/R module from being affected by electromagnetic interference,it is usually necessary to add an absorber for electromagnetic shielding,and the absorber will affect the electrical performance of the microstrip isolator in the T/R module.Taking a microstrip isolator working in K-band as the object,absorbing material was set above the permanent magnet by using the experimental cavity,the magnetic induction intensity and suction force of the permanent magnet at different heights from the absorbing material,and the electrical performance of the isolator were investigated.The results show that when the distance of the absorbing material is 2mm above the permanent magnet,the electrical performance of the K-band microstrip isolator is basically not affected,which provides a reference for the spatial design of the spatial design of the magnetic shield absorbing plate in T/R module.