Flammulin, an anti-tumor protein, was purified from the aqueous extract of basidiomes of Flammulina velutipes. The purification process included ammonium sulfate and ethanol fractionation, DEAE-Sephadex A-50 and CM-Sephadex C-50 ion-exchange chromatography. Flammulin was purified to electrophoretic homogeneity and crystallized by microdialysis. With a molecular mass of 23 700, pI 8.9,�� max=276��278 nm,�� min=250 nm, flammulin was characterized by its lack of Met.. The product was found to have marked anti-tumor effect on Sarcoma 180 and Ehrlich ascites tumor. No toxicity has been detected.