Objective To investigate the correlation between early blood pressure variability （BPV） and functional prognosis in patients with small artery occlusive （SAO） stroke. Methods A total of 136 cases of acute SAO stroke patients who conformed to the standard in our hospital from October 1， 2019 to September 30， 2020 were selected. General clinical data of the patients were collected， including NIHSS score， age， sex， history of hypertension， history of diabetes mellitus or HbA1c， hyperlipidemia， history of coronary heart disease， history of smoking， history of alcohol abuse， past history of stroke， and baseline data that antithrombotic medication during hospitalization. Blood pressure parameters were collected through 24-hour ambulatory blood pressure monitoring. According to the modified Rankin score （mRS） 3 months after stroke， all patients were divided into good prognosis group （mRS ＜ 3 points） and poor prognosis group （mRS ≥ 3 points）. The general clinical data and blood pressure parameters of the two groups were compared. Binary logistic regression was used to analyze the relationship between BPV and neurological prognosis. Results Compared with the good prognosis group， the NIHSS score， the history of diabetes， the difference between the maximum and minimum systolic blood pressure （SBPmax-min）， the 24-hour systolic blood pressure coefficient variability （24 h-SBPCV）， the day systolic blood pressure coefficient variability （dSBPCV） and the night systolic blood pressure coefficient variability （nSBPCV） were all increased in the poor prognosis group， with a statistically significant difference （P ＜ 0.05）. Binary Logistic regression analysis showed that 24 h-SBPCV （OR=0.629， 95%CI：0.424-0.932， P=0.021）， dSBPCV （OR=1.590， 95%CI：1.053-2.401， P=0.028）， high NIHSS score at admission （OR=3.309， 95%CI：1.845-5.937， P=0.001）， diabetes history （OR=0.203， 95%CI：0.075-0.549， P=0.002） is a risk factor for poor prognosis of neurological function in small artery occlusive stroke. Conclusions High NIHSS score at admission， diabetes and the increase of 24 h-SBPCV and dSBPCV are the independent risk factor for poor neurological prognosis of small artery occlusive stroke.