This study aimed to test the “healthy immigrant” hypothesis and assess health heterogeneity among newly arrived working-age immigrants (18–64 years) from various regions of origin. Using the 5% sample of the 2000 U.S. Census (PUMS), we found that, compared with their native-born counterparts, immigrants from all regions of the world were less likely to report mental disability and physical disability. Immigrants from selected regions of origin were, however, more likely to report work disability. Significant heterogeneity in disabilities exists among immigrants: Those from Eastern Europe and Southeast Asia reported the highest risk of mental and physical disability, and those from East Asia reported the lowest risk of physical disability. Furthermore, Mexican immigrants reported the lowest risk of mental disability, and Canadian immigrants reported the lowest risk of work disability. Socioeconomic status and English proficiency partially explained these differences. The health advantage of immigrants decreased with longer U.S. residence.