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To investigate the effect of different tillage methods on soil organic carbon pool, straw returning apparent humification coefficient and maize yield, an eight-year（2008—2015）field experiment with six tillage measures under straw returning in dark loessial soil on Loess Plateau was conducted. The tillage measures included three single continuous tillages (no-tillage (NN), subsoiling (SS) and conventional tillage (CC)), and three rotational tillages (no-tillage-subsoiling (NS), subsoiling-conventional tillage (SC) and conventional tillage-no-tillage (CN)). The results showed that compared with the conventional tillage, the measures of NN, SS and rotational tillage increased the content of soil organic carbon (SOC), microbial biomass carbon (MBC), water-soluble organic carbon (WSOC) in 0~10cm soil layer, improved the ratios of MBC to SOC and WSOC to SOC. Although there was no significant difference in the hardly oxidized carbon (HOC) content for different treatments in 0~10cm soil layer, the ratio of HOC to SOC was increased by SS, NN and rotational tillage in the soil layer of 10~20cm, 35~50cm and 20~35cm, respectively. The store of HOC was increased significantly in the NN treatment in 0~50cm soil layer. Compared with conventional tillage, the yield of corn and the dry mass of corn straw were increased in the treatments of SS, NN and rotational tillage, the maximum increment was found to be in the treatment of NS, by 13.79% for grain yield and 12.04% for straw dry mass, respectively. After eight-year straw returning, the apparent humification coefficient of straw in conventional tillage treatment was 8.94%,，which was lower than those in the treatments of NN, SS and rotational tillage. The apparent humification coefficient of returning straw was 14.09% in the NS treatment, which was the highest among all the treatments. Based on soil carbon pool and corn yield, the tillage of NS was the most suitable measure for the local soil conditions.