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In order to deal with the problems of straw returning and soil tillage in multiple cropping rice regions of paddy-upland rotation in mid-lower Yangtze River, and reduce the power consumption and axial force of the existing interlaced-type rotary blade roller, a research about arrangement and structure parameters of the helical blades in combined cutter roller was conducted. Based on the theoretical analysis of the axial force of cutter roller, two arrangements for balancing axial forces were proposed and verified by discrete element software. The simulation results showed that the axial load stability and cutting resistance of herringbone arrangement were better than that of serrated and interlaced type. Based on the principle of herringbone type arrangement, the rotary blades ware rearranged and the supporting cutter plate was designed. In order to further reduce the power consumption of the cutter roller, the mathematical model of cutting soil with helical blades was established. Based on the mathematical model, the influence of installation angle and blade width on cutting resistance and straw burying effect was analyzed, and the optimization of the installation angle and blade width was carried out accordingly. Field tests were carried out to verify the applicability and drag reduction effect of the optimized cutter roller. The testing results showed that the optimized cutter roller was suitable for straw returning and soil tillage for most paddy fields, and the average tillage depth was 18.10cm, the stability of the tillage depth was 92.75%, the smoothness after tillage was 2.00cm, and the straw buried rate was 92.60%, which can all meet the design requirements. The results also showed that without reducing the straw buried rate, the power saving range of the herringbone-type rotary blade roller was 0.34%~17.01% compared with the interlaced-type rotary blade roller，and the power saving range of the blade roller assembling helical blades with 50° installation angle was 6.81%~16.46% compared with helical blades with 35° installation angle, which verified that the proposed blade roller can achieve the aim of optimization. The research result provided new technical equipment for the direct full amount of straw returning to the field.