Objective　To study the relationship between cognitive impairment and hypercholesterolemia as well as the risk factors thereof in elderly patients with white matter lesions (WML). Methods　A total of 347 WML patients were divided into normal cognitive group (n=86) and cognitive impairment group (n=261) according to their mini-mental state examination (MMSE) score. The general situation of the two groups was compared and the correlation of hypercholesterolemia with WML severity and cognitive function was analyzed; the risk factors of cognitive impairment in WML patients were analyzed by logistic regression analysis. Results　Compared with those in normal cognitive group, the patients in cognitive impairment group were older, the plasma low-density lipoprotein (LDL) level and the proportion of male, low education level, hypertension and hypercholesterolemia were significantly higher (P<0.05), while MMSE score and the proportion of patients with a history of statins were significantly lower (P<0.05). The proportion of patients with cognitive impairment significantly increased (P=0.001), and the incidence of hypercholesterolemia also increased significantly (P=0.000) with the increasing of WML severity. The Montreal Congnitive Assessment (MoCA) score, visuospatial and executive function, attention and computing power, language and abstract ability, and delayed recall scores of patients with hypercholesterolemia were significantly lower than that of patients without hypercholesterolemia (P<0.05). Logistic regression analysis showed that low education level, hypertension, hypercholesterolemia and the higher level of plasma LDL were independent risk factors of cognitive impairment in patients with WML (P<0.05), while the history of statins use was a protective factor (P<0.05). Conclusion　Hypercholesterolemia can significantly increase the risk of cognitive impairment in patients with WML, thus the WML patients with hypercholesterolemia should be focused, and various risk factors should be controlled, at the same time the fortified early intervention is necessary. DOI: 10.11855/j.issn.0577-7402.2016.12.08