Objectives: To evaluate the occurrence of dental caries among 5- and 12-year-old children in Northeastern Italy and to compare dental status between immigrants and native-born children. Basic research design and participants: A cross-sectional survey of 260 5-year-olds and 862 12-year-olds was carried out between October 2003 and May 2004. Dental caries were diagnosed at the caries into dentine (D3) threshold. Differences in dental health status were compared between immigrant and native-born children for both age groups. Results: Among 5-year-old children, mean dmft was 1.45 (SD=2.69), SiC=4.31, 65.8% had no caries. Immigrant 5-year-olds (6.2%) scored more poorly than their Italian counterparts: mean dmft was 5.12 (vs. 1.21; p<0.001) and only 25.0% were caries free (vs. 68.4%; p<0.001). Among 12-year-olds, mean DMFT was 1.44 (SD=2.00), SiC=3.88, 55.1% had DMFT=0: 5.6% also had poorer dental status: mean DMFT was 3.23 (vs. 1.33; p<0.001), SiC=6.69 (vs. 3.66), and only 17.1% had DMFT=0 (vs. 56.8%). Conclusions: The prevalence of dental caries and care obtained for both age groups are similar to those of other industrialised countries. When our results for 12-year-olds were compared with those of two previous surveys (1984 and 1994), a major decline in the prevalence of dental caries was observed. Being immigrant was a strong determinant in caries occurrence. Key words: children, dental caries, immigrants , Italy, prevalence