The Kinshasa region, drained by an important hydrographic network, contains streams beds made of sandpits for the supply of sand as building materials. This study has consisted of a granulometric characterization of these sandy materials. A single source of sediment is at the origin of these sandy deposits with medium sand as characteristic facies. With a moderately strong regular flow, a mesokurtic distribution of frequency curves, an asymmetry towards fine grains and a good to fairly good grading of grains, the sandy deposits of stream beds of Kinshasa have a fluviatile character. The positive correlation observed between medium grain and the grading index certifies the gradual refinement and good ranking of grains observed in these sandy deposits. The dominant pink color of the sandy deposits of Kinshasa rivers indicates that these deposits are devoid of organic matter.