Objectives: to examine knowledge and opinions amongst first and third year nursing students toward adequate antibiotic usage. The goal of this study is to examine is there difference regarding to year od study (first or thrid), employment, finished high school and grade in course Farmacology. Study Design: Study was conducted as cross-sectional. Participants and Methods: The study included 101 first and third year nursing students. Study was conducted at Faculty of Medicine in Osijek during May and June of 2016. For this purpouse self-constructed anonymous questionnaire was used that contains 38 questions. Statistic analyses was done in computer program R. Results: Significant statistic differences regarding year of study is noticed in particle “Antibiotics are prescribed to ease the pain”(Mann Whitney U p=0,009), where first year students tend to have more positive opinion. Third year studentsignificantly think more positive about statement: „Antibiotics are prescribed to ease the infection“ (Mann Whitney U p=0,025). Also significant statistic differences are noticed in particle: “ Desloratadine is new generation of antibiotics”(Mann Whitney U p=0,024), where first year students think more positive, as well as on statement “Paracetamol is in group of antibiotics” (Mann Whitney U p=0,001). There is no significant statistic differences regarding employment, finished high school and grade in course Farmacology. Conclusion: Students's opinions and knowledge about adequate antibiotic usage differ only regarding year of study. Regarding employment, finished high school and grade in course Farmacology significant statistic differences does not exist.