Background The scientific, professional, and social challenges of the modern world are disease prevention and preventive programs. The new century is the century of vaccination, which aims to eradicate, control, and eliminate numerous life – threatening infectious diseases. Vaccination is considered one of the most successful and effective medical interventions of modern medicine in prevention of accelerating the incidence and spread of infectious diseases and at the same time a fundamental human right of every human being. Aim To examine the knowledge of undergraduate and graduate nursing students about vaccines, the vaccination calendar in Croatia and personal vaccination status. Methods The research was conducted among nursing students at the Croatian Catholic University in Zagreb during June 2022. The sample consisted of a total of 106 students who voluntarily and anonymously filled out the questionnaire. The data was collected through an online questionnaire that was sent to the students’ university e – mail addresses. The survey questionnaire included questions about socio – demographic characteristics and personal vaccination status, questions that examined knowledge about vaccines and the vaccination calendar in Croatia, and questions about the appropriate knowledge acquired at the university. The results It was established that the nursing students at the Croatian Catholic University have a relatively high level of knowledge about vaccines and the vaccination calendar in Croatia, regardless of the level and regularity of the study program. Conclusion The research encourages further research into the knowledge of nursing students about vaccines and the vaccination calendar in Croatia, including other nursing students from other universities in Croatia, to obtain a clearer and more complete picture with which to act on the education of healthcare professionals in the field of infectiology and immunology.