Abstract: The kinds of materials used in the circuit analogue, the size of the circuit analogue and the electromagnetic parameter influencing the properties of the microwave absorbing composite were studied for the microwave absorbing composite material systems in "trap" type and gradually changed resistance type. The research results show that the microwave absorbing property is improved by 3~5 dB in the frequency range of 8~18 GHz. The microwave absorbing property with the thickness of 4 mm is more than 12 dB in the frequency range of 8~18 GHz. The introduction of circuit analogue into the structural design of the microwave absorbing composite improves not only the wave absorbing properties, but also the mechanical properties. So it is feasible to apply circuit analogue in the design of microwave absorbing composites.