Abstract: In order to study the influence of penetrative wire terminal load to cavity electromagnetic coupling, a model of cavity with penetrative wire and load was set up by finite integration time domain method(GTEM). By changing the terminal load and connection style, the coupling law of enclosure was analyzed through SE parameter; a new experimental system based on GTEM chamber was developed, the numerical results were approved well. The results indicate that when the terminal load is resistance or capacitive, the coupling of cavity is descended with the load connected to cavity or cavity connected to ground, the coupling effect is obviously influenced by the value of resistance or capacitive load. Comparing resistance load with capacitive load, the SE of cavity has no change at low frequency when the load is not connected to ground and open, the same situation appears at high frequency when the load connected to ground and short. The resonance frequency is influenced by the load connecting to cavity.