AimsTo determine whether sharing the same ethnicity as their family physician influenced the quality of diabetes care for Chinese and South Asian patients in Ontario, Canada. MethodsWe conducted two related studies: a population-based cohort study of Chinese and South Asian patients with incident diabetes using health care administrative data (n=49,484), and a cross-sectional study of Chinese and South Asian patients with established diabetes using data collected directly from their family physicians’ clinical records (n=416). In both studies, quality of care measures were compared between patients whose family physicians were or were not from the same ethnic group. ResultsIn the cohort study, Chinese patients whose family physicians were also Chinese were more likely to have a diabetes-related family physician visit and appropriate HbA1c and cholesterol testing. In the cross-sectional study, they were more likely to have foot examinations, to have microalbuminuria testing, and to achieve recommended treatment targets for HbA1c and for LDL-cholesterol. In contrast, for South Asian patients, most quality measures in either study did not differ by physician ethnicity. ConclusionsHaving a family physician from the same ethnic group was associated with better quality of diabetes care for Chinese but not for South Asian patients.