Poly(vinylidene fluoride) (PVDF) hollow fiber membrane used as the matrix was hydrophile-modified by alkali and hydroxyethyl-cellulose(HEC) treatment in this paper. After being activated and coupled, the PVDF hollow fiber affinity membranes with phenylalanine as the ligand were prepared. XPS analysis was used for measuring the changes of chemical structure on the membrane surface. The results indicated that on the membrane surface oxygen and nitrogen contents increased from 5. 6% to 16. 5% and 0. 6% to 3. 0...