Diabetic gangrene is a non-healing skin ulcer that is often resistant to most common treatments. It is caused by microvascular disorders and an immunocompromised state which are induced by diabetes mellitus. We report a 65-year-old man with an aggressive, refractory diabetic gangrene on his left foot. Treatment of his diabetic gangrene with topical application of a mixture of peripheral blood mononuclear cells (PBMC) and basic fibroblast growth factor (bFGF) resulted in a dramatic improvement in a short time. The ulcer was completely closed and, in the past 6 months, no new ulceration has been observed. The patient is able to stand and walk by himself. Topical application of a mixture of PBMC and bFGF appears to be a useful, non-invasive and convenient method for the treatment of diabetic gangrene.