To evaluate cognitive function in cerebral small vessel disease (CSVD) patients without dementia and explore the correlation between the number and location of cerebral microbleeds (CMBs) and the impairment of cognitive function． Methods: A total of 174 consecutive patients with CSVD were prospectively recruited. All patients underwent MRI-susceptibility weighted imaging (SWI) to evaluable CMBs, and the location and number of CMBs were recorded. Patients were divided into the CMBs group (62 cases) and non-CMBs group (112 cases) and evaluated by the Montreal Cognitive Assessment (MoCA) scale to compare cognitive function scores between the two groups. The relationship between the location and number of CMBs and cognitive function scores was analyzed by partial correlation analysis and Spearman’s correlation. Results: The frequency of cortical-subcortical and deep and infratentorial CMBs were 40.87% (132/323) and 59.13% (191/323), respectively. There was a predilection for CMBs occurrence in the basal segment (31.27%), thalamus (12.07% ), frontal lobe (12.69% ), and temporal lobe (10.84% ). Compared to the non-CMBs group, the CMBs group showed a decrease in MoCA total score, visuospatial and executive function, attention, abstract thinking, delayed recall, and orientation (P<0.05); there was no significant difference between the two groups in naming and language scores (P>0.05). The number of CMBs was negatively correlated with the MoCA total score, attention, and delayed recall (r=－0.260, P=0.028; r=－0.242, P=0.039; r=0.228, P=0.049). Cortical-subcortical CMBs was negatively correlated with the MoCA total score, visuospatial and executive function, attention, and delayed recall (r=－ 0.278, P=0.019; r=－ 0.231, P=0.045; r=－ 0.213, P=0.049; r=－ 0.234, P=0.035). Deep CMBs was negatively correlated with the MoCA total score and attention (r=－0.254, P= 0.019; r=－0.239, P= 0.028). Conclusion: CMBs may lead to impaired cognitive function in patients with CSVD, particularly affecting executive function, attention, and delayed recall. Patients experience increased impairment when there is an increase in microbleeds detected. CMBs may serve as a biomarker of CSVD with a significant role in the early diagnosis and prognosis of vascular dementia.