The increasing concern on global warming and climate change has resulted in a special awareness to the potential of forest and soil for sustainable carbon sequestration. Therefore, an optimal management of afforestation established in barren lands notably influences the soil carbon sequestration which consequently turns the forest coverage (and underlying soil) to a major organic carbon sink. This study aims to quantify the amount of carbon storage in a selected area afforested Black Locust in Malayer, Iran. Initially, the land units including Black Locust trees were indicated on map polygons, followed by the measurement of all trees within the polygons. Then, five samples in each diameter class were selected, within which the amount of biomass, carbon storage and co2 uptake were estimated. To determine the amount of stored carbon in the soil, samples were collected from two soil depths of 0-10 and 10-30 cm. The amount of the annual sequestrated carbon in biomass and soil was then estimated to be 0.351 and 1.253 tons per ha, respectively. In addition, the annual co2 uptake was 5.87 tons per ha. The results indicate significant differences between the amount of carbon storage in different diameter classes of R. pseudoacacia trees