Objective: This study examined relationships between anticholinergic medication burden and brain integrity in people living with HIV (PLWH) and people without HIV (HIV-). Methods: Neuropsychological performance z-scores (learning, retention, executive function, motor/psychomotor speed, language domains, and global cognition), and neuroimaging measures (brain volumetrics and white matter fractional anisotropy) were analyzed in PLWH (n ¼ 209) and HIV- (n ¼ 95) grouped according to the Anticholinergic Cognitive Burden (ACB) scale (0 ¼ no burden, 1 – 3 ¼ low burden, >3 ¼ high burden). Neuropsychological performance and neuroimaging outcomes were compared between HIV- and PLWH with high anticholinergic burden. Within a cohort of PLWH (n ¼ 90), longitudinal change in ACB score over ~2 years was correlated to the rate of change per month of study interval in neuropsychological performance and neuroimaging measures. Results: A higher number of anticholinergic medications and ACB was observed in PLWH compared with HIV- (P < 0.05). A higher ACB was associated with worse motor/psychomotor performance, smaller occipital lobe, putamen, subcortical gray matter and total gray matter volumes in HIV-; and poorer executive function, retention and global cognition, smaller brain volumes (frontal, parietal and temporal lobes, hippocampus, amygdala, cortex, subcortical gray matter and total gray matter), and reduced fractional anisotropy (posterior corpus callosum, perforant pathway) in PLWH. PLWH with high anticholinergic burden performed worse on tests of learning and executive function compared with HIV- with high anticholinergic burden. Longitudinally, PLWH who reduced their ACB over time had better neuropsychological performance and neuroimaging measures. Conclusion: Anticholinergic medications were associated with worse neuropsychological performance and reduced structural brain integrity, and these effects were more widespread in PLWH. Use of anticholinergic medications should be carefully monitored in older adults with deprescription considered whenever possible.