Medieval glazed ceramics, dated to the early 15th century, excavated at the Belgrade Fortress, Serbia, was investigated combining optical microscopy, X-ray powder diffraction (XRPD), scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS), micro-Raman spectroscopy and multivariate statistical analysis. Decoration and style of investigated ceramics were characteristic of workshops from different areas of medieval Serbian state: Ras, Krusevac and Belgrade/Smederevo. Comparison was made with ceramic samples from the same period excavated at the Studenica Monastery, the earliest workshop discovered so far, which were used as reference material for Ras area. Ceramics from the Belgrade Fortress was covered with transparent, lead-based glaze. Majority of the glazes were produced by application of mixture of lead oxide and quartz to the clay body, whereas only two samples were glazed by application of lead oxide by itself. Brown colours of the glaze originate from Fe-based spinel, whereas copper and iron were responsible for the coloring of the green and yellow glazes. The obtained results revealed glazing technology taken from Byzantine tradition.