Considering the outstanding biocompatibility of Bombyx mori silk fibroin, this study is designed to fabricate biomimetic nanofibrous structure made of silk fibroin, which can enhance cell activities for tissue formation. The electrospinning of blend of silk fibroin with low molecular weight poly(ethylene-oxide) (PEO) is explored with ease of preparation for high productivities. The average diameter of electrospun silk fibroin (eSF) is decreased from 414 +/- 73 to 290 +/- 46 nm after PEO extraction. To induce the desired cellular activity, the surface of the eSF fibers is modified with fibronectin by using the carbodiimide chemistry method. The potential use of the obtained wound healing material is assessed by indirect cytotoxicity evaluation on normal human dermal fibroblast (NHDF) in terms of their attachment and cell proliferation. The surface-modified eSF nanofiber mats show good support for cellular adhesion and spreading as a result of fibronectin grafting on the fiber surface, especially for cell migration inside the fibrous structure. These results demonstrate a new fabrication technique of surface-modified silk fibroin electrospun nanofibers for biomedical application; with the ability to accelerate wound healing. (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3634-3644, 2013