Based on a long-term experiment during 1979—2014 with various fertilizations in black soil of northeast China, the objective of this study was to research evolution characteristics of soil organic carbon (SOC) content, carbon sequestration and its cooperation with carbon input. The results showed that: Compared to the initial soil condition, SOC content in long-term chemical fertilizers application (N, NP, NPK, N2) decreased by 11.6%～16.1%, while the SOC content in long-term horse manure application significantly increased. Chemical fertilizers application plus horse manure with conventional application rates (MNP, MNPK) or doubleness (M2N2, M2N2P2) could increase SOC content 6.5%, 8.4%, 7.7% and 11.6%, respectively. The carbon sequestration in the treatment of non-fertilization (CK) and chemical fertilizers application appeared deficit, ranged from 3.5～6.1 t/hm2. In contrast, SOC storage in the treatment of chemical fertilizers application plus horse manure showed surplus, and the maximum value was 1.9 t/hm2 (M2N2P2). There was a significantly positive linear correlation between annual average organic C input and C sequestration efficiency, which showed that black soil still had potential carbon sequestration. The calculated annual transform rate of input carbon was about 34.1%, and the least carbon input for maintaining the initial organic carbon level was about 1.416 t/hm2. Therefore, increasing carbon input (manure) was a key to improve carbon sequestration in black soil region.