This work consists of a sedimentological and paleoenvironment study of the carbonate rocks of the Mbuji-Mayi Supergroup dated to the Neoproterozoic of the Bena Kabongo quarries. Macroscopically, two lithofacies have been determined, namely: limestone and dolomite. Field observations show us that the base of the sequence is dominated by dark fine-grained limestones. The summit part is represented by fine-grained gray limestones that alternate with brownish dolomite. Based on seven thin sections, a microscopic observation was carried out and allowed us to detect three microfacies, namely: intrasparites, intramicrites and intraclastics, all representing a standard sequence of the sedimentary series. This sequence shows the evolution of the deposit going from a subtidal zone to an intertidal zone. Analysis of the microfacies of the sequence shows that the strata were accumulated on an internal ramp in the shallower and more oxidizing conditions with stromatolitic flora.