Based on the 2009 Thematic Household Survey in Hong Kong, this study compared health status and utilization of health care services in Hong Kong between migrants from Mainland China and natives. Overall, Mainland migrants reported lower socioeconomic conditions, worse health status, and less health care services utilization than the natives. After controlling for socio-demographic factors, we found that the migrants were 1.2 times more likely to report fair or poor health and 0.78 times less likely to report having a usual source of care, compared with the natives. Mainland migrants also had fewer physician visits and relied more on the public sector. Within the migrant group, those who had language advantage had more visits, and the recent arrivals who stayed in Hong Kong for three years or less had fewer visits and were far less likely to have a usual source of care. The findings underscore migration as an important social determinant of health in Hong Kong. A combination of targeted social and health policies is needed to help Mainland migrants better integrate into society and to improve their access to care. Programs should be tailored to address varying needs from different subgroups among migrants.