In coping with the shortage of deceased kidney donors, living donor kidney transplantation is mainly performed in Japan. We started our living unrelated spousal kidney transplantation program in 1989. In this analysis, we compared the results of 64 spousal transplantations performed between September 1989 and May 2007 with those of living related and deceased donor grafts. Despite the older age of the recipients and the lower HLA matching, the graft survival rates of spousal transplants were as good as those from living related donors and better than those from deceased donors, (P < .01). The graft survival rate of spousal kidney transplantation is improving with advances in immunosuppression, so spouses are considered important donors in Japan, which lacks deceased donors.