Abstract: Suberogorgin(Sub) was shown to increase the tension of isolated guinea pigtrachea in a dose dependent manner. Its ED50 was 52.5μmol·L^-1. The stimulation of sub ontrachea was antagonized by atropine 0.65μmol·L^-1, and inhibited by atropine 0. 13μmol·L^-1,cobrotoxin2.4μg· mL^-1 and by tetrodotoxin lμmol·L^-1. On the contracted trachea induced bygalanthamine 35.5μmol·L^-1 , acetylcholine increased the tension but Sub dIu not. Galanthaminewas also shown not to increase the tension of trachea that had been treated with Sub 258μmol·L^-1for 10 min. The results indicate that the trachea-excitant action of Sub is related to the M and Nreceptor and the Na⁺ channel.