Twelve dogs were used for the experiment of allograft of the trachea. Under general anesthesia, the cervical trachea in the donor was exposed and five or six segments of cartilage were excised, and then, these grafts were transplanted at the central portion of the cervical trachea in the recipient. For the effective vascularization, the omental pedicle was transplanted around the graft. The immunosuppressant was administered in 5 dogs. In the experimental results, 5 dogs were survived over 30 days and one dog is now alive over 9 months with good condition. Postoperative bronchofiberscopic observation demonstrated that the formation of granulation occurred one week after transplantation and the stenosis developed and exacerbated by infection. In the long survived dog the anastomotic stenosis disappeared and the color of the mucosa of the graft was same as the recipient's. It was considered that the blood supply at the anastomotic portion was the most important factor for the viability of allograft of the trachea.