This study examines the physical health status of immigrants with specific considerations of Asian and Hispanic populations and explores possible mechanisms through which health outcomes of interest can be explained. Analyses of the National Health Interview Surveys (NHIS) of 2000 and 2001 revealed that foreign-born individuals reported fewer chronic diseases (hypertension, heart disease, asthma, cancer and diabetes) and had lower prevalences of various chronic diseases compared with U.S.-born whites, controlling for possible confounders and mediators. However, U.S-born minority groups did not show the health advantage seen in foreign-born immigrants, reflecting the importance of nativity distinctions in studying immigrant health. Despite having fewer chronic diseases, foreign-born Asians were more likely to rate their health negatively relative to their U.S.-born counterparts and to U.S.-born whites. In addition, our findings provide evidence that failure to consider comorbid status may attenuate the nativity effect on certain chronic diseases.