Abstractobjectives Refugees and immigrants are likely to be vulnerable to mortality from infectious diseases as a result of high prevalences in their countries of origin and barriers in access to healthcare in the recipient countries. Consequently, we aimed to compare and investigate differences in mortality from infectious diseases among refugees and immigrants and native Danes.methods A register-based, historical prospective cohort design. All refugees (n = 29 139) and familyreunited immigrants (n = 27 134) who, between 1 January1993 and 31 December1999, were granted the right to reside in Denmark were included and matched 1:4 on age and sex with native Danes. Civil registration numbers were cross-linked to the Register of Causes of Death, and fatalities owing to infectious diseases (based on ICD-10 diagnosis) were identified. Mortality ratios were estimated separately for men and women by migrant status and region of birth; adjusting for age and income; using a Cox regression model, after a mean follow-up of 10-12 years after arrival.results Female [hazard ratio (HR) = 4.15; 95% CI: 2.38, 7.25] and male (HR = 2.05; 95% CI: 1.27, 3.33) refugees experienced significantly higher mortality risks from infectious diseases than did native Danes, as was the case for male immigrants (HR = 2.39; 95% CI: 1.20, 4.76) but less so for female immigrants (HR = 1.23; 95% CI: 0. 50-3.01). Mortality by region of origin was notably higher for individuals from North Africa and sub-Saharan Africa.conclusions Higher mortality among refugees and immigrants than among the native population should lead to reflections on medical reception systems in recipient countries and subsequent possibilities of access to specialised diagnostic and curative healthcare.