In the Constitution of the Republic of Croatia, the framer of the Constitution defines and prescribes the highest values of the constitutional order of the Republic of Croatia, which also form the basis for the interpretation of the Constitution. The highest values of the constitutional order are binding for all subjects that implement the Constitution of the Republic of Croatia, from the legislative, executive and judicial branches to the Constitutional Court of the Republic of Croatia. The rule of law is one of the highest values of the constitutional order of the Republic of Croatia. The Croatian Constitution recognises that all the highest values of the Croatian constitutional order are of equal value. In concrete cases, however, there may be contradictions between individual values, so it is necessary to find the right balance between them. Another characteristic of the highest values of the Croatian constitutional order is the fact that the Constitution does not define their content in detail. Their content is identifiable, but not explicit. All subjects that implement the Constitution are obliged to interpret it on the basis of the highest constitutional values. However, only one of these bodies, the Constitutional Court, enjoys such a constitutional status that enables it to interpret these values, and this interpretation, which is expressed in its decisions, has a generally binding force erga omnes. In its jurisprudence, the Constitutional Court of the Republic of Croatia has in several cases encountered the need to decide what it understands by the rule of law, as one of the highest values of the constitutional order of the Republic of Croatia. On the basis of its constitutional jurisdiction and its constitutional status as the guardian and protector of the Constitution, the Constitutional Court has expressed in several of its decisions what it considers to be the rule of law. These positions of the Constitutional Court are highly important for the implementation and protection of the rule of law as one of the highest values of the constitutional and legal order of the Republic of Croatia. In this paper, I will examine the concept of the rule of law as the highest value of the constitutional legal order from a theoretical perspective, as well as the case law of the Constitutional Court of the Republic of Croatia, which also includes its activist role in defining the content of this value.