The last two decades a huge progress has taken place in the field of the primary prevention of infections and many new vaccines have been introduced in the compulsory vaccination program. There is evidence, however, that immunization coverage against some infectious diseases is not adequate. Aim: It was to investigate the level of immunization coverage of Greek and Immigrants' children aged 4-12 years old in the prefecture of Evritania regarding vaccines against pertussis-diphtheria-tetanus (DTaP), poliomyelitis (IPV) and measles–mumps–rubella (MMR). Material and methods: The sample of the study consisted of the pupils of all nursing and elementary schools of the prefecture of Evritania , aged 4-12 years old. Children's personal Health Cards were used to evaluate the adequacy of vaccine doses. X2 was usedfor comparisons. Statistics was processed with SPPS 17.0. Results: The boys of the sample were 469 (51.9%) and the girls 434 (48.1%). Full vaccination coverage with DTaP, MMR and IPV was 87.3%, 79.9%, and 97.6% respectively. No statistically significant differences were observed between Greek and Immigrants' children. Conclusion: Vaccination coverage against measles, mumps and rubella was inadequate. Immigrants' and Greek children are equally covered. Vaccination coverage with MMR is troublesome.