The objective of this study was to observe the healing of skin and mucosal grafts, comparing with the control sites. Six adult dogs were divided into two groups of three. Mucosal defects were created in all four quadrants, and the left side was used as a control. In the Group I animals, a split-thickness skin from the chest was grafted, and in the group II animals, a split-thickness mucosa from the buccal cheek was grafted into the mouth. Gross and microscopic examination was done at 3, 7, 14, 28, 42 days. The results were as follows. 1. Wound epithelization was accelerated in the supraperiosteal grafts. 2. After healing, the grafted skin was unnatural to the oral cavity, showing grayish-white color, hair, and sebaceous gland. But the mucosal grafts could not be discriminated from the adjacent mucosa. 3. the grafting on the cortical bone failed.