Knowing, learning and proper use of mother tongue is very important for every person as a individual and for society in general. Language is a tool of communication needed for receving and sending informations and mother tongue is something we are recognizable, something that marks us from the earliest age. Taking all these facts into consideration teaching of mother tongue, as a formal form of learning it, is taking the most important role in the educational system. The aim of this thesis is to analyze and compare organization and implementation of mother tongue teaching in primary education in Croatia and Sweden. The comparison is largely based on the prescribed documents according to which the teaching is organized, but also by examples from the teaching practice itself. A still valid document in Croatia, Teaching Plan and Program for Elementary School will be compare to a swedish National Curriculum under which teaching in Sweden is organized. Apart from the documents that organize the teaching proces, performance of the classes and the evaluation of pupils' achievements are compared too. Taking the curricular reform that is currently happening in Croatia into consideration, the paper gives an insight into this document as well, showing its positive and negative sides and how more similar it is to the Swedish model of education. The thesis concludes that there are more differences than similarities in organizing and implementing teaching of mother tongue in primary education in these two contries. Sweden has been applying a more modern concept of the curriculum for a number of years so it can serve as an example for curricular reform that is happening in Croatia, but also we need to take cultural, economic, industrial and social differences between these two contries into consideration.