［Objective］ To investigate the effects of Epimedium Icariine on activity of isolated small intestinal smooth muscle from rabbits.［Method］ The routine experimental method of small intestinal (duodenum) smooth muscle isolated from rabbits is used to put in homothermal smooth muscle and connect with tension pickup, signal are input into BL-420E biological function experiment system, then add with different concentrations of Epimedium Icariine solution, the automatic contracting characteristic and changing law in taking Epimedium Icariine before and after are recorded. ［Result］ Epimedium Icariine of different density (10-4, 10-3, 10-2 mol/L)have a restraining effect on automatic contracting activity of isolated small intestinal smooth muscle whose scope have remarkable differences comparing to taking ethanol before and after.［Conclusion］ Epimedium Icariine has a direct inhibitory trend on small intestine smooth muscle. _