The subject of this paper is the analysis of the institute of real security through the period of Roman legal history, since when they first appeared with a final comparison with what they mean and are today. The advanced thinking of Roman jurists and their entire legal apparatus is demonstrated through the analysis of the Roman law institutes of fiducia, pignus and hypotheca. The Roman legal system brought into use institutes that regulated various aspects of legal relations that took place between people. From the first regulations in which they were mentioned, then the famous Roman jurists who thematized them in their legal opinions, those three institutes are elaborated in this paper according to their purpose, meaning, operation and legal protection, including revolutionary Roman lawsuits such as actio Serviana, actio quasi Serviana, etc. After the interpretation of the Roman understanding of the aforementioned institutes, the work continues in the direction of major codifications of civil law in the XIX century and the XX century, primarily Austria and Germany, whose civil codes had the greatest influence on the further legal development and the Croatian interpretation of the same institutes. Through part of the history, the long-term connection of Croatian legal culture with the Austrian general civil code is revealed, which will clarify the appearance of Roman foundations in Croatian laws. The task of this paper is to show the importance of Roman law in the part that relates to the creation and application of instruments of real security and to show how powerful it is, when through two thousand years of various changes and progress that the world likes to brag about today, law actually always returns to its Roman beginnings.