Abstract: OBJECTIVE To observe the effects of extractive from Acanthopanacis Cortex on contraction of mice intestinal smooth muscles in vitro and explore the possible mechanisms. METHODS To observe the effect of different dosage on the spontaneous activity of intestinal smooth muscle in mice. Acetylcholine, CaCl₂ or KCl were investigated. RESULTS Extractive from Acanthopanacis Cortex exerted an inhibitory effect on the contraction induced by Ach and KCl, also on the spontaneous activity, the effect was dose-dependent in 0.8-4.0 mg·mL^-1. CONCLUSION The mechanism of the inhibition of Acanthopanacis Cortex is the contraction of mice intestinal smooth muscles resembles the mechanism of atrophine, which is irrelevant with voltage dependent calcium channel.