Poly-L-lactide (PLLA) has been used to prepare scaffolds to guide tissue regeneration in tissue engineering research. However, one of the limitations to the use of PLLA as an ideal biomaterial is its high hydrophobicity. To improve the hydrophilicity of PLLA, hydrophilic polymers were grafted onto PLLA membrane surfaces through the combination of photooxidization in hydrogen peroxide and subsequent ultraviolet (UV)-induced grafting copolymerization in the monomer solution. Three kinds of modified PLLA membranes (i.e., PLLA-g-polyhydroxyethyl methacrylate, PLLA-g-polyacrylamide, and PLLA-g-polymethacrylic acid) were obtained, resulting in the more wettable PLLA membranes. The occurrence of the grafting polymerization was confirmed by attenuated total reflectance infrared spectroscopy (ATR-IR) and X-ray photoelectron spectroscopy (XPS) analysis. Surface morphology of the modified PLLA membranes was studied by scan electronic microscopy (SEM).