The deodorizing responses of the steam distillate from some medicinal plants(G-3) on three representative malodors were evaluated by estimating the best estimate threshold(BET) of odor responses. With a single spray of G-3, the BETs of malodors such as ammonia, acetic acid, and ethyl acetate were found to increase 4.11, 32.6 and 13.1 fold, respectively, which indicated G-3 possessed a potent deodorizing activity. The deodorizing potency of G-3 was also demonstrated to be as high as and even higher than those of the commercial deodorizing agents.