Objective:To analyze the result of smooth pursuit test(SPT) in unilateral vestibular peripheral vertigo and investigate its influencing factors.Method:Smooth pursuit test (SPT) and spontaneous nystagmus (SN)were examined in one hundred and eighty-five patients with unilateral peripheral vertigo(case group) and 51 normal persons(control group) by Video-Nystagmography (Synapsys, France), and the gain of SPT and SN were selected as the observation parameters in order to analyze the waveform and gain of SPT and the relativity between SN and the gain of SPT.Result:Of the 185 patients, 105(56.8%),72(38.9%) and 8(4.3%) cases producedⅠ,Ⅱ and Ⅲ waveforms respectively. Of these patients, 58(31.4%) demonstrated SN and none had Ⅳ waveform. While of 51 normal persons, 38(74.5%), 13(25.5%) persons producedⅠand Ⅱwaveforms repectively and there were no Ⅲ, Ⅳ waveforms or SN. There was statistical significance between the stong and weak gain of SPT in these two groups. Weak gain was significantly different between two groups. The stong and weak gain of SPT in case group were 0.86±0.06,0.80±0.06; 0.78±0.09, 0.65±0.1; 0.68±0.13, 0.45±0.12. The relativity between SN and the gain of SPT was positive when they had same direction(r_s=-0.63,P＜0.05)and negative when opposite (r_s=0.34,P＜0.05).Conclusion:Ⅰ,Ⅱ,Ⅲ three waveforms of SPT could appear in unilateral vestibular peripheral vertigo and the corresponding gains are gradually decreasing.SN is the influencing factor of SPT.