A case of Hippocratic digital associated with secondary hypertrophic osteoarthropathy complicating Crohn's disease in a 29 year old Japanese male is reported. Hippocratic digital, or finger clubbing, complicating inflammatory bowel disease has been frequently reported in the Western hemisphere. However, its association with secondary hypertrophic osteoarthropathy has been very rarely found in that disease. In Japan, Hippocratic digital has not been described previously. With regard to the pathogenesis of Hippocratic digital and secondary hypertrophic osteoarthropathy, the theory that both entities belong to the same pathological spectrum and that megakaryocytes or platelet clumps may play the most important role, is discussed.