Аннотация:The accumulation of the contemporary surface dirt and dust sediments is an important problem of an urban area. The surface dirt sediment is deposited on the various surfaces both inside and outside the residential blocks. The sediment represents the secondary and nonpoint pollution source due to the presence of the environmental toxicants, heavy metals and pathogens in their content. The aim of the study was to determine the mineral phase composition of surface sediment in the city of Ekaterinburg in order to identify the sources of its origin. The 60 samples of surface sediment were collected in summer at the different parts of residential blocks (traffic ways, sidewalks and lawns, inner yard area, parking lots, and green areas). The sediment samples were fractionated by the particle size fractions: 0.002-0.01 mm, 0.01-0.05 mm, 0.05-0.1 mm, 0.1-0.25 mm, 0.25-1 mm and >1 mm. The particle size fractions were analysed by X-ray diffraction. According to the results of analysis the investigated mineral composition of the surface sediments represent the complex multi-phase mixtures, similar in mineral composition (quartz, microcline, plagioclase, magnetite, chlorite etc.). The sources of the mineral component in the surface sediment were identified.