Objectives: This study aimed to examine ethnic disparities in the prevalence of diabetes and its association with sleep disorders among the older adults Han and ethnic minority (Bai, Ha Ni, and Dai) population in rural southwest China. Methods: A cross-sectional survey of 5,642 was conducted among the rural southwest population aged >= 60 years, consisting of a structured interview and measurement of fasting blood glucose, height, weight, and waist circumference. The Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality. Results: The overall prevalence of diabetes and sleep disorder was 10.2% and 40.1%, respectively. Bai participants had the highest prevalence of diabetes (15.9%) and obesity (9.9%)(P < 0.01), while Ha Ni participants had the lowest prevalence of diabetes (5.1%) and obesity (3.4%)(P < 0.01). The highest prevalence of sleep disorder (48.4%) was recorded in Bai participants, while Dai participants had the lowest prevalence of sleep disorder (25.6%)(P < 0.01). In all four studied ethnicities, females had a higher prevalence of sleep disorder than males (P < 0.01), and the prevalence of sleep disorder increased with age (P < 0.01). The results of multivariate logistic regression analysis indicated older adults with sleep disorder had a risk of developing diabetes (P < 0.05). Moreover, the higher educational level, family history of diabetes, and obesity were the main risk factors for diabetes in participants (P < 0.01). Conclusion: There are stark ethnic disparities in the prevalence of diabetes and sleep disorders in southwest China. Future diabetes prevention and control strategies should be tailored to address ethnicity, and improving sleep quality may reduce the prevalence of diabetes.