The article is devoted to the results of archaeological investigation of barbican – one of the strategic points of fortification in the Belgorod-Dnestrovskyi fortress. In spite of being of Eastern origin, barbican became one of the types of defensive structures in Europe. The typological and chronological periodization of the building of Belgorod’s barbican includes the following stages. It was constructed in the XV century on the territory of the Moldavian Principality all together with the Low Wall, as part of the early period of the history of the fortress. Similar to the other European barbican buildings of the same time in Torun, Krakow, Lvov, it represents the structure of the tower type. The tower is connected with the main room of barbican through the gallery; the entrance was discovered in the course of excavation. The square of the earliest structure of barbican is about 250 m2. The reconstruction of barbican took place in the Ottoman period of the fortress, as part of the bastion system connected with the further development of artillery. The main elements of the first phase of building, such as of the tower and the planning in the trapezoid shape can be seen on gravures of the beginning of the XIX century.