Abstract: By using water a kind of antiseptic from Cloyodendron Cvrtophyuan which could be added into feed was extracted.By means of filter paper disks tests the antimicrobial effect of Cloyodendron Cvrtophyuan’s extract were verified and then.The extract’s antimicrobial efficeney on Staphylocooous and Penieillium was taken as the measurements in this experiment. After orthogonal design and experiments, the optimal extract process gualifications are extractive ratio is 1:20, circumfluencetemperture is 100℃, circumfluence time is 40min, The marium absorbing peak is 270nm. Cloyodendron Cvrtophyuan haveobvious antimicrobial actions on bacteria and mod . The lowest antimicrobial level for Staphylococcus aureus is 0.055%(ml/100m), Aspergillus flavus and Penicillium is 0.55%(ml/100m),Escherichia coliform and Bacillus subtilis is 2.77%(ml/100m).

Key words: Cloyodendron cvrtophyuan, optimal extract process, antimicrobial action, the lowest antimicrobial level