Background: Despite the inconsistent findings of the growing amount of research analysing the possible health consequences of temporary employment, there is a lack of heterogeneous perspectives. The aim of the study was to analyse whether the health consequences of temporary employment are worse among low educated compared with high educated, after control for health-related selection. Methods: A 26-year follow-up study of a cohort of all school leavers in a middle-sized industrial town in northern Sweden was performed between 1981 and 2007. Of those still alive of the original cohort, 94% participated during the whole period. For this study, a sample of participants with temporary and permanent employment contracts between the age of 30 and 42 years was selected (n = 660). Results: In multivariate logistic regression analyses, an additive synergistic interaction effect was found for low education and high exposure to temporary employment in relation to suboptimal self-rated health, after controlling for health-related selection and sex. An additive antagonistic interaction was found between low education in combination with high exposure to temporary employment in relation to psychological distress, whereas no interaction was found for depressive symptoms. Conclusion: Our hypothesis regarding worse health effects of temporary employment among low educated was partly confirmed. Our results indicate the need to analyse temporary employment from a more heterogeneous perspective as well as in relation to different health outcomes.