Background & Objective: Since dysfunctions of autonomic nervous system are thought to play a major role in the pathogenesis of vasovagal syncope(VVS), we analyzed the function of autonomic nervous system by means of heart rate variability(HRV), and evaluated whether the different types of vasovagal syncope could be associated with different cardiac autonomic pattern. Methods: we evaluated 86 patients that underwent head-up tilt (HUT) test, and measured HRV. Patients with atrial fibrillation, frequent(720>24hour) atrial premature beat, or ventricular premature beat were excluded. 69 patients had a negative HUT test(NEG), 6 patients were vasodepressor-type VVS(VD-VVS), and 11 patients were other type (mixed & cardioinhibitory) VVS(O-VVS). Time-domain indices (SDNN, SDANN, RMSSD, pNN50, HRV index) of HRV were measured by using a 24-hour Holter recording. Results: Patients with VD-VVS had lower values of SDANN than those with O-VVS(p=0.10). Other parameters of HRV were not different between two groups. Conclusion: we conclude that (1)patients with VD-VVS have trend of lower SDANN, (2)SDANN, which is an estimate of long term components of HRV (low frequency variation) is mediated by sympathetic nervous system. Therefore, it is suggested that VD-VVS may be associated with sympathetic dysfunction.