Objectives. We studied mortality differentials between specific groups of foreign-born immigrants in Sweden and whether socioeconomic position (SEP) could account for such differences. Methods. We conducted a follow-up study of 1 997 666 men and 1 964 965 women ages 30 to 65 years based on data from national Swedish total population registers. We examined mortality risks in the 12 largest immigrant groups in Sweden between 1998 and 2006 using Cox regression. We also investigated deaths from all causes, circulatory disease, neoplasms, and external causes. Results. We found higher all-cause mortality among many immigrant categories, although some groups had lower mortality. When studying cause-specific mortality, we found the largest differentials in deaths from circulatory disease, whereas disparities in mortality from neoplasms were smaller. SEP, especially income and occupational class, accounted for most of the mortality differentials by country of birth. Conclusions. Our findings stressed that different aspects of SEP were not interchangeable in relation to immigrant health. Although policies aimed at improving immigrants’ socioeconomic conditions might be beneficial for health and longevity, our findings indicated that such policies might have varying effects depending on the specific country of origin and cause of death.