Objectives: Poor self-rated health is an estimator of quality of life and a predictor of mortality seldom studied in immigrant populations. This work aimed to study self-rated health in relation to social capital, socioeconomic status, lifestyle and comorbidity in immigrants from Iraq - one of the largest non-European immigrant group in Sweden today - and to compare it with the self-rated health of native Swedes. Design: The study was a cross-sectional population-based study conducted from 2010 to 2012 among citizens of Malmo, Sweden, aged 30-65 years and born in Iraq or Sweden. All participants underwent a health examination and answered questionnaires on self-rated health, social capital, comorbidity, lifestyle and socioeconomic status. Results: In total, 1348 Iraqis and 677 Swedes participated. Poor self-rated health was identified in 43.9% of Iraqis and 21.9% of native Swedes (p<0.001), with the highest prevalence (55.5%) among Iraqi women. Low social capital was highly prevalent in the immigrants. Female gender showed higher odds of poor self-rated health in Iraqis than in Swedes (OR 1.8, 95% CI 1.4-2.5, p(interaction)=0.024), independent of other risk factors connected to social capital, socioeconomic status, lifestyle or comorbidity. Conclusions: Although public health initiatives promoting social capital, socioeconomic status and comorbidity in immigrants are crucial, the excess risk of poor self-rated health in Iraqi women is not fully attributed to known risk factors for self-rated health, but remains to be further explored.