In the present contribution, the ultrafine fiber membranes of polyhydroxybutyrate (PHB) and organic-soluble chitosan(O-CS) was prepared by electrospinning. The structure and thermal stability were studied by infrared (FTIR) and thermogravimetric analysis (TG). The surface properties of ultrafine fibers were estimated by contact angle measurements using water. The morphology was observed by scanning electron microscopy (SEM). The cytotoxicity assessment with mouse fibroblast cells (L929) was also investigated. Cell culture results showed that it benefits promoting the cell attachment and proliferation. The results showed it could be as tissue engineering for skin regeneration. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 118: 3619-3624,2010