The paper begins by defining the concept of the referendum and its main forms, as well as by establishing the criteria of their differentiation. It analyses the basic characteristics of the existing legal framework of the referendum in the Republic of Croatia prescribed by the Constitution of the Republic of Croatia, the Act on the Referendum and Other Forms of Personal Participation in the Exercise of Government Power and Local (Regional) Self-Government and the Act on Local and Regional Self-Government. Based on the Constitutional Act on the Constitutional Court of the Republic of Croatia, which regulates the holding of civil-initiative referendums, the Constitutional Court decides whether the meaning of a referendum question conforms with the Constitution and whether the requirements for the calling of the referendum have been met. The paper also discusses the amendments to the constitutional and legislative referendum framework of the Republic of Croatia from its adoption up to 2019, as well as the recommendations of the legal standards of the Venice Commission Code of Good Practice on Referendums. Through the Amendments to the Constitution of 2000, the civil-initiative referendum was introduced into the Croatian legal framework. For the referendum to be called on the national level, signatures must be collected within fiften days and their number must not be lower than ten percent of the total number of registered voters. The paper also discusses the method and procedure of voter declaration on the need for demanding the calling of a referendum, as well as the procedure of verifying the number and authenticity of voter signatures. Special emphasis is placed on the subjects and constitutional limitations of referendum-based decision-making and on the principle of clarity of the referendum question and its subsequent rephrasing. The strict requirements for calling a referendum have so far resulted in a small number of held referendums. Out of the three national referendums that have been held, only one was initiated by voters. Mentioned in the paper are fifteen local referendums, although their exact number is unknown due to the lack of official records on them.