BACKGROUND: In diabetes mellitus patient with general anesthesia can be especially quite fatal if autonomic neuropathy were involved in the autonomic nervous system of cardiovascular system. This research was designed to study for incidence of diabetic autonomic neuropathy(DAN) in diabetic patients and to check the effects of the cardiovascular system by general anesthesia in DAN patients. METHODS: DAN was diagnosed by 5 different diagnostic criterias and that criterias were suggested by Ewing and Clarke. For evaluation of the effects between autonomic neuropathy and general anesthesia in diabetes patients with DAN, systolic blood pressure, diastolic blood pressure, heart rates were measured on 5 points from start of anesthesia to 5 minutes prior to completion of operation, and was checked about incidence of dysrhythmias and using of vasopressor drugs during anesthesia. RESULTS: Incidence of DAN were 11 cases within 33 diabetes patients. Among the 11 cases, 10 cases developed neuropathy in parasympathetic nervous system and 3 cases developed neuropathy in sympathetic nervous system. There were no statistical significance of the changes of systolic blood pressure, diastolic blood pressure and heart rate between control group and DAN patients under general anesthesia except just after intubation. Also, the incidence of dysrhythmias and using vasopressors during anesthesia were checked and compared. CONCLUSIONS: We concluded as follow. 1) It is essential to the safe anesthetic managements that diabetes patients are anesthetized after having diabetic autonomic function test before anesthesia. 2) If we are going to do general anesthesia for DAN patient, anesthesiologist have to pay more vigilance on the change of blood pressure and pulse rate, especially on just after intubation period.