Objective To investigate the inhibition of Eriobotryae Folium from twenty different districts towards phosphodiesterase 4(PDF4) in vitro.Methods The Eriobotryae Folium were extracted with 95% ethanol reflux and the inhibition rates against PDE4D2 were carried out by liquid scintillation counting method.Results All the samples exhibited inhibitory activities towards PDE4 at 5 mg/L.Among them,nine samples were of the inhibition rate less than 80%,eleven samples were of more than 80% inhibition and eight samples were of more than 90% inhibition.Conclusion The Eriobotryae Folium shows significantly different inhibitory activities towards PED4.