Abstract: OBJECTIVE To investigate the effect Curcuma Rhizoma on rat duodenum smooth muscle contraction and its mechanisms. METHODS After isolated rat duodenum samples were prepared, it was observed that the effect of Curcuma Rhizoma at different concentrations on rat duodenum smooth muscle contraction using BL-420 biological and functional experimental system with constant perfusion way. It was observed that the effect of Curcuma Rhizoma at different optimum concentrations on smooth muscle contractile amplitudes induced by atropine, norepinephrine, isoproterenol, verapamil respectively. Dose-effect curve of different concentrations of neostigmine on intestinal contraction was recorded, comparing with that of Curcuma Rhizoma group. Cholinesterase activity was detected so as to assisting the proof that whether its one of mechanisms is similar to that of neostigmine. RESULTS Curcuma Rhizoma facilitated significantly rat duodenum smooth muscle contraction in a dose-dependent manner; Curcuma Rhizoma antagonized partly the inhibitory effect on intesinal smooth muscle induced by a M receptor blocker(atropine), β receptor agitator(isoprenaline), calcium channel blocker(verapamil). However, it did not act on α receptor(norepinephrine). Its action was similar to that of the acetylcholin esterase activity which was inhibited by acetylcholin esterase inhibitor(neostigmine). CONCLUSION The mechanisms of its effect may be mediated by M receptors by inhibiting cholinesterase. It also may be related to inhibition of α and β receptor.