Objectives <p>Finding the associations between cohabitation status and sleep quality in caregivers of people with dementia (PLwD) was the goal of this study.</p> Methods <p>This cross-sectional study included 230,900 adults who participated in the 2024 Korean Community Health Survey (KCHS). Sleep quality evaluated by the Pittsburgh Sleep Quality Index (PSQI) were compared between 3,709 cohabitating caregivers of PLwD, 21,080 non-cohabitating caregivers of PLwD, and 206,111 non-dementia caregivers. Multiple logistic regression were performed to evaluate the relationship between the cohabitation status caregivers of PLwD and sleep quality measured using the PSQI and PSQI subcomponents.</p> Results <p>Cohabitating and non-cohabitating caregivers of PLwD group was significantly poor psychosocial variables (stress, depression assessed by Patient health questionnaire-9 (PHQ-9)) and higher prevalence of poor sleep quality (PSQI score ≥ 6). than non-dementia caregivers. Multivariable logistic regressions adjusted for potential confounders revealed that cohabitating caregivers of PLwD (odds ratio (OR) 1.17, 95% confidence interval (CI) 1.13–1.20) and non-cohabitating caregivers of PLwD (OR 1.12, CI 1.04–1.20) were significantly associated with poor sleep quality. In addition, PSQI subcomponents showed that sleep quality (OR, 1.16; 95% CI, 1.03–1.31), sleep latency (OR, 1.14; 95% CI, 1.06–1.22), sleep duration (OR, 1.11; 95% CI, 1.07–1.15), sleep efficiency (OR, 1.25; 95% CI, 1.12–1.39), sleep disturbance (OR, 1.13; 95% CI, 1.01–1.26), sleep medication use (OR, 1.61; 95% CI, 1.44–1.80) and daytime dysfunction (OR, 1.41; 95% CI, 1.32–1.51)) were associated with cohabitating caregivers of PLwD.</p> Conclusion <p>Our results showed that both cohabitating and non-cohabitating caregivers of PLwD experienced overall poorer sleep quality compared to non-dementia caregivers.</p>