Cultured skin autografting has promise to improve the prognosis of severe burn injury. Established methods for cultured epithelial cell autografting need enzymatic proteolytic reaction that have potential risks of losing cell surface structures and causing allergic reactions in the recipients. Therefore, we have developed an enzyme-free method of cultured skin autografting. Donor skin was obtained in 0.2-0.3 mm thickness during an operation of debriding burned eschar. The skin was cut into pieces and spread on removable soft culture surface membrane in culture plates. Modified MCDB 153 medium with 10 microg/L epidermal growth factor and 150 mg/L bovine pituitary extract was used. The tissues were incubated at 37 degrees C in a water-saturated atmosphere of 5% CO2 in air. After 3 weeks, the cultured tissue on the membrane was removed mechanically from the bottom of the plates and implanted on granulated recipient sites in upside down manner. The cultured auto-skin grafting was successfully performed in two patients with severe burn. The recipient sites were partially epithelized in 2 weeks and maintained thereafter. Our method is performed easily using partial thickness donor skin without enzymatic processes.