Molecularly imprinted composite membranes for selective binding of erythromycin were synthesized by means of UV initiated photo-copolymerization method using polysulfone ultrafiltration (PSF) membranes as porous supports.The thin imprinted layers deposited on the surface of the support membranes were formed by eopolymerization of acrylic acid (AA) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as cross-linker in the presence of erythromycin as template molecule in acetonitrile solution.Fouder transform infrared spectroscopy (FT-IR) spectroscopy was used to study the binding mechanism between the imprinted sites and the template.Scanning electron microscope (SEM) was utilized to visualize surface and cross-sections of membranes to gain more better understanding in the analysis of imprinted layers deposited on PSF support membranes.The modification degrees for imprinted and non-imprinted membranes are 2.04 and 2.15 mg/cm2,respectively.Static equilibrium binding and recognition properties of the imprinted and non-imprinted membranes to erythromyein (EM) and its analogue roxithromyein (RM) in aqueous system were tested.The results showed that saturated binding capacity of imprinted membranes to erythromyein was about 1.85mg/cm2,nearly 8 times of that of non-imprinted one,and the selectivity factor of αEM/RM was 3.24.The results of this study implied that the synthesized molecularly imprinted composite membranes could be used as selective separation materials for erythromyein enrichment from water.