A biological tissue sheet which is expected as exerting a favorable therapeutic effect and a high safety in transplantation. The biological tissue sheet formed by (a) preparing in vivo-derived cells; (b) sowing the in vivo-derived cells on amniotic membrane; and (c) culturing and proliferating the in vivo-derived cells in the absence of any xenogeneic animal cells. As the cells of a biological origin, for example, cells originating in corneal epithelium, conjunctival epithelium, skin epidermis, hair follicle epithelium, oral mucosa, respiratory tract mucosa, or intestinal tract mucosa.