Compulsory education is a prerequisite for formal education, and in countries around the world it has a different duration and characteristics, compulsory education usually refers to elementary school. This paper compares compulsory education in the Republic of Croatia and Ukraine. Compulsory education in the Republic of Croatia lasts 8 years, while in Ukraine it lasts 9 years. Along with a review of the literature, valid laws and regulations, a comparison of the national curricula for compulsory education in Croatia and Ukraine was made. This comparison revealed differences in the number of compulsory subjects taught in primary schools and in the number of teaching hours of individual subjects between Croatia and Ukraine. The topic of this thesis is the comparison of the educational systems of the Republic of Croatia and Ukraine, so the work is divided into two parts, the first part is theoretical, and the second part is a comparison of the educational systems of the two countries. In this thesis, taking into account the determinants of content, an analysis of five subject areas of primary education taught in both countries was carried out. Comparing the current characteristics of the content reveals that the same or similar content is taught in Croatia and Ukraine. A comparison was also made about the method of assessment, teaching materials and teacher education.