In this study, poly(L-lactide) ( PLLA) non-woven mats were prepared by electrospinning technique, followed by treating with oxygen plasma and grafting with 3-aminopropyl triethoxysilane (APTES), then immersed in poly(gamma-glutamic acid) (gamma-PGA) solution to form a layer of gamma-PGA on the surface. In so doing, hydrophobic PLLA would become highly hydrophilic. Through characterization of hydrophilicity and biocompatibility, the feasibility of these modified mats for wound dressing was evaluated. The results show that after the grafting of gamma-PGA, the swelling ratio increased greatly from 7% for pristine PLLA mat to 321% for gamma-PGA-grafted PLLA mat, and the contact angle decreased from 112 degrees to 25 degrees. In vitro cytocompatibility tests against L929 fibroblast show that gamma-PGA-grafted PLLA was non-cytotoxic. In addition, the proliferation of fibroblasts was higher on gamma-PGA-grafted PLLA than on pristine PLLA.