Abstract: Mineralization of soil organic carbon (SOC) is an essential process of biochemistry in soils, which is closely related to terrestrial ecosystem carbon cycle and global climate change. It is important toadopt reasonable tillage and nutrient management to improve the carbon accumulation and sequestration potential in soil. With the context of carbon sequestration and emission reduction, it is urgent to explore the relationship between tillage and nutrient management and SOC stability. Therefore, in order to clarify the effects of tillage and nutrient management on SOC mineralization in fluvo-aquic soil of North China. Based on a 15-year long-term positioning experiment of tillage and nutrient management (2007—2022), two main treatments were set: rotate plow without straw return (RP-S), deep plow with straw return (DP+S), and three scondary treatments were set: controlled fertilization (CK), Conventional fertilization (CON), Optimized fertilization (OPT), with a total of six treatments. Soil samples were collected at 0～20 cm depth in October 2022. The contents of SOC and activated carbon components, carbon pool management index were analyzed. SOC mineralization rate were determined by incubation method. First-order kinetic model was used to calculate potential mineralization and turnover rates. The structural equation model were fitted to reveal the turnover and sequestration rule of soil organic carbon under different tillage and nutrient management.Years of experiments have shown that under the condition of RP-S, C/N(SOC and TN ratio) generally showed a decreasing trend, while under the condition of DP+S, C/N generally showed a increasing first and then decreased trend. The results showed that compared with rotate plow without straw return (RP-S), deep plow with straw return (DP+S) treatments increased the contents of activated carbon components in soil, and the carbon pool management index (CPMI) increased significantly. Compared with CON, OPT significantly increased the content of SOC, with incremental rates of 12.35%. OPT significantly increased the readily oxidizable carbon (ROC) and CPMI with the condition of DP+S. SOC mineralization rates were the highest in the 1 d and then decreased rapidly. After 10 d incubation, it decreased slowdown and until it stabilized. The changes of SOC mineralization rate were in agreement with the logarithmic function relationship. Nutrient management enhanced the mineralization rates of soil organic carbon in the fluvo-aquic soils in the following order: OPT>CON>CK. SOC mineralization rate in all treatments were consistent with the first-order kinetic model. DP+S significantly increased the cumulative mineralization rate (value of C₀/SOC) by 23.59%, while OPT significantly reduced the value of C₀/SOC by 22.12%. The accumulative mineralization of SOC(C_t) was significantly and positively correlated with SOC, activated carbon components and soil carbon pool management index(P<0.01), both were significantly and positively correlated with Potential mineralizable of SOC(C₀) in fluvo-aquic soils(P<0.05). Tillage management, microbial biomass carbon (MBC) and ROC were the directly factors of SOC mineralization and sequestration potential in soil. Tillage and fertilization management can affect SOC mineralization by the contents of SOC and activated carbon components, and then impacting soil carbon sequestration potential. Based on the results of SOC accumulation content, the direct positive impact of long-term deep plow with straw return treatment on soil carbon sequestration potential had been completely counteracted the indirect negative effect of the increase in SOC and activated carbon components on soil carbon sequestration potential. In conclusion, Long-term DP+S with OPT significantly improved stability of soil structure and increase SOC sequestration potential and Optimized fertilization reduce the cumulative SOC mineralization rate of soil, enhanced the SOC accumulation and sustainable utilization of farmland resources which could be suggested as an ideal management scheme on farmland to optimize the combination of tillage and fertilization in fluvo-aquic soil of North China.