Objective To investigate the effects of butylphthalide soft capsule on the expression of uric acid and the pathological changes of white matter in patients with moderate and severe leukoaraiosis.Methods A total of 60 patients with moderate to severe leukoosteoporosis admitted to the department of neurology of People's Hospital of Hai'an City,Jiangsu province from May 2021 to November 2022 were selected and divided into a study group and a control group by random number table method.The control group was treated with conventional basic treatment,and the study group was treated with butylphthalein softgel based on the control group.The score of mini-mental state examination(MMSE)scale,montreal cognitive assessment(MoCA)scale,hachinski ischemia score(HIS)scale,total decline scale(GDS),the levels of plasma factors[homocysteine(Hcy),total cholesterol(TC),central nervous specific protein(S100β)and uric acid(UA)]and improvement in leukoencephalopathy[as measured by arterial flow velocity at peak systolic flow rate(Vs),end-diastolic peak flow rate(Vd),and mean peak flow rate(Vm)]before and after treatment were compared between the two groups.Results A total 60 patients with leukoaraiosis were included,with 30 cases in the study group and 30 cases in the control group,respectively.Before treatment,there were no significant differences in scores of MMSE,MoCA,HIS and GDS,levels of Hcy,TC,S100β and UA,Vs,Vd,and Vm between the two groups(P＞0.05).After treatment,the scores of MMSE and MoCA scores,Vs,Vd,and Vm on both sides were significantly higher than those before treatment(P＜0.05),and those in the study group was significantly higher than those in the control group(P＜0.05);the scores of HIS and GDS,and the levels of Hcy,TC,S100β and UA were significantly lower than those before treatment(P＜0.05),and those in the study group was significantly lower than those in the control group(P＜0.05).Conclusions Butylphthalide soft capsule in the treatment of moderate and severe leukoaraiosis can effectively reduce the cognitive impairment,restore the cognitive function,reduce the levels of plasma factors,improve the cerebral blood flow,and improve the condition of leukoaraiosis.