Soil organic matter has gradually decreased since the original reclamation of black soil in Northeast China, and the organic carbon pool has maintained a deficient state for an extended period, which in theory leads to a greater carbon sequestration potential. Based on sloping farmlands (30-60 a) in a typical black soil area, the organic carbon distribution characteristics of different soil layers (topsoil and subsoil) at different slope positions (upper-slope eroded area and lower-slope deposit area) were investigated. Besides, the sequestration potential of organic carbon on sloping farmlands with different reclamation years and duration to meet the carbon sequestration potential were estimated. The results showed that: (1) the total organic carbon, the organic carbon density, and the carbon saturation level in lower-slope deposition areas and in the topsoil layer were significantly greater than those in upper-slope eroded areas and subsoil layer, respectively. All their maximum values were found to occur on sloping farmland with 30 years of reclamation. (2) The carbon sequestration potential of upper-slope eroded areas (1.24-2.89 kg/m²) and subsoil (0.83-3.59 kg/m²) was significantly higher than that of lower-slope deposition areas (0.79-1.04 kg/m²) and topsoil (0.6-2.53 kg/m²), respectively. The potential of carbon sequestration was significantly lower in farmland with 30 years of reclamation than that in farmlands with 40 years and 60 years of reclamation. (3) It will take 20-181 a and 13-66 a to achieve carbon sequestration potential in upper-slope eroded areas and lower-slope deposition areas of sloping farmland (30-60 a) in black soil (0-50 cm), respectively. Therefore, more attention should be paid to the spatial-temporal variability of carbon sequestration potential on sloping farmland in the process of agricultural operation and restoration management, to realize the sustainable potential of black soil resources.