Several studies have demonstrated that immigrants in Scandinavian countries are more affected by psychosocial disabilities than the native-born population. The aim of the study was to evaluate the possible impact of work-related stressors on psychiatric health in immigrants compared to native Swedes. The study included a cluster selected cohort of 1,040 men born in 1944 (participation ratio = 79.9%), living in Gothenburg, Sweden. Of these, 182 (18.0%) were immigrants, defined as being born outside Sweden. Information on work conditions and psychiatric health were obtained by self-administered questionnaires. Employment in native Swedes showed inverse associations to frequent use of anxiolytics [relative risk (RR) = 0.2; 95% confidence interval (CI) = 0.06-0.4], frequent use of hypnotics (RR = 0.1; CI = 0.02-0.2) and use of antidepressants (RR = 0.3; CI = 0.2-0.5). None of the employed immigrants used anxiolytics or hypnotics frequently. Swedes seemed to display a number of psychiatric ill-health factors related to working conditions. These factors included frequent use of hypnotics, frequent insomnia, use of antidepressants, a high degree of melancholy, and were related to shift work, dissatisfaction with current work and management and a low degree of influence on work situation, often related to a high degree of stress at work and a frequent desire to change type of work. These associations were not seen in immigrants, apart from the risk of frequent insomnia (RR = 4.7; CI = 1.2-18.3) and dissatisfaction with colleagues (RR = 10.4; CI = 2.2-48.8) when working in shift. With a few exceptions, non-optimal working environment was associated with a low degree of life satisfaction in both groups. It was hypothesized that optimal working conditions are important for maintaining psychiatric health, and that immigrants, when employed, seem less affected by impaired working conditions than native Swedes.