Abstract: Nano-scale particles of silk fibroin peptide(SFP) were prepared by a three-step process: dissolving silk fibroin fiber in special solvents,followed by dialysis and concentration,and finally enzymolysis withα-chymotrypsin.Screening test was performed with 4 kinds of solvents and experimental results showed that LiBr/ CH3OH/H2O mixed solvent achieved the best effect.The size of SFP particles appeared about 20-50μm,and that of SFP nano-scale particles were about 80-300 nm.SFP nano-scale particles revealed better antibacterial activity than SFP particles.