This study examines health differences between first-generation immigrant and Canadian-born persons who share the same the ethnocultural origin, and the extent to which such differences reflect social structural and health-related behavioural contexts. Data from the 2000/2001 Canadian Community Health Survey show that first generation immigrants of Black and French race/ethnicity tend to have better health than their Canadian-born counterparts, while the opposite is true for those of South Asian, Chinese, and south and east European and Jewish origins. West Asians and Arabs and other Asian groups are advantaged in health regardless of country of birth. Health differences between ethnic foreign- and Canadian-born persons generally converge after adjusting for socio-demographic, SES, and lifestyle factors. Implications for health care policy and program development are discussed.