The aim of this population-based study was to assess the incidence rates of infectious diseases in native- (Italian) and foreign-born (immigrants) populations in a North Italy area, in 2006-2010. Crude, age-specific incidence rates (IRs) and age-standardised rate ratios (SRRs) between foreign- and native-born subjects and their 95% confidence intervals (95% CI) were estimated. A total of 32,554 cases of infectious diseases were found (9.9% in foreign-born subjects). The highest SRRs between foreign- and nativeborn subjects were found for tuberculosis (SRR = 27.1; 95% CI 21.3-34.3), malaria (SRR = 21.1; 14.6-30.4), scabies (SRR = 8.5; 7.6-9.4), AIDS (SRR = 2.5; 1.8-3.4) and viral hepatitis B (SRR = 3.3; 2.1-5.2). The highest IR was found for AIDS in people from the Americas (IR = 4.57; 95% CI 2.2-8.4), for malaria and tuberculosis in people from Africa (IR = 13.89; 11.6-16.5 and IR = 11.87; 9.8-14.3 respectively). Therefore immigrants are at a higher risk of acquiring some common infectious diseases compared to the native population in Western European countries.