The goal of this paper is to analyse the system of state authority in the Republic of Croatia. The paper is made up of seven chapters. The state authority in Croatia is divided into legislative, executive and judicial power. The introduction describes the term of a state and power, as well as the power in the Republic of Croatia in particular, whilst the second chapter focuses on the term of the division of power, its historical development and the distinction in terms of its functions and organization. The chapter on the division of the power in the Republic of Croatia provides the list of reasons for transition from a semi-presidential system into a parliamentary system in 2000. The fourth chapter defines the legislative power and its holder (Croatian Parliament), its capacity and powers as well as the concept of Ombudsman. The fifth chapter depicts the holders of executive power, their powers, their interrelations and the definition of public administration and the bodies of both local and regional self-government. The sixth chapter depicts the organisation of judicial power in the Republic of Croatia and defines the most important bodies of judicature and their functions. The last chapter encompasses the conclusions.