The adsorbability of NOx on various adsorbents, La_0.2Sr_0.8Co_1.0Ox (LSC) supported on H-ZSM-5 and ion-exchanged Co/ZSM-5, has been studied by microwave-induced adsorption-desoption cycle. The allowable temperature of LSC supported on H-ZSM-5 was changed with the loading amounts of LSC. Among the adsorbents, Co/ZSM-5 showed best adsorbaility of NOx was not changed with increasing the number of adsorption-desorption cycle.