Objective: The aim of this work was to show vaccine coverage in the Republic of Croatia, as well as to improve the diseases against which theVaccine Immunization Program is being vaccinated. Methods: The retrospective research on prevalence has covered data at the level of the entire Republic of Croatia in the preliminary vaccination from 2012 to 2017 and there vision in 2017. Also processed are the number of death and suffered of illnes obligation calendar immunization. Results: In the observed period from the first vaccination from 2012 to 2017, we notice that in 2015 we have a fall in the combined vaccine "6 in 1" drop below the 95% minimum prescribed by law. What continued in 2017. An exception is the vaccine coverage of MPR vaccines, which are continuously below 2012, below 95%. BCG vaccines do not fall below 98%. With the seizure of sixty-year-olds against tetanus, a minimum vaccine coverage of 90% was not achieved. Even in 2014 we have only 41.6% vaccinated. The numbers of sick and dying of infectious diseases against which the Program of Mandatory Immunization in the Republic of Croatia indicate a favorable condition. During the observed period there is no disease of polyomyelitis and diphtheria. By the end of 2014 there is a measles epidemic and 14 cases of illness are recorded, which continues in 2015 when we have 206 reported cases, 2016 we have 4 cases, while 2017 we have 7 cases of illness from this contagious disease. Concluson: Vaccination coverage are the main indicators of the success of the immunization program. Execution of the Program is mandatory for all citizens in the Republic of Croatia. Despite all the scientific evidence of vaccine benefits, we have a fall in vaccine coverage at the state level and the level of collective immunity is compromised. The negative trend of fall in vaccine coverage can be overcome by strengthening the anti-vacinal movement. There is currently no abstinence from the diseases that the Program for compulsory immunization is supposed to take, but since we are dealing with migrations and mating, we need to work to raise awareness of the need for vaccination in which a nurse has a big role. By educating within their compensation and by knowing the evidence of vaccine safety and nursing nursing security, it does not raise awareness of the individual but of the entire population. The outbreak of measles epidemic warns us of the importance of maintaining high vaccine coverage in the country as well as the importance of a coordinated approach to health professionals in combating contagious diseases.