Remains of wall paintings and stucco ornaments add to our knowledge of Singidunum. Fragments of wall paintings found at the crossing of Tadeuša Košćuškog and Gospodar Jovanova Streets represent the earliest known paintings in the territory of Belgrade. Traces of classical paintings and stucco ornaments have also been found in the Lower Town of the Belgrade Fortress, in Knez Mihailova Street, on Studentski Square and Kosančićev Venac.
The preserved fragments of painted wall decoration feature geometric designs, imitations of marble facing, floral ornaments and figural representations. Birds, executed with great skill and with a fine sense of detail, are a common motif of classical wall paintings in the interior of public or private buildings, as well as of sepulchral wall paintings. The pigments used were red, pale ochre, blue, pale green, grey, brown and black. Fragments of painted wall plaster which bear traces of gold colour indicate the existence of luxurious Roman buildings, such as might have been the one in Kosančićev Venac, in which remains of floor mosaics were also discovered. The wall surfaces were usually divided into vertical and horizontal zones by painted borders or wall mouldings, which have also been discovered on these sites. Some stucco decoration imitated architectural elements, such as pilasters, capitals, arches, and cornices.