Due to the lack of management, Camellia oleifera forests would encountered problems such as soil compaction and mixed growth of grass and shrubs. In order to achieve integrated operations of soil loosening, weeding, and clearing shrubs in low and intensive Camellia oleifera forests, a vertical spiral machine for soil loosening and weeding was developed. The vertical spiral cutter was designed by analyzing the physical and mechanical characteristics of common weeds and miscellaneous shrubs roots in Camellia oleifera forests, and combined with motion analysis of cutting tools. The root-soil composite model was established by using Hertz-Mindlin bonding contact model, with the goal of reducing power consumption, the parameters of the cutting tool were simulated and optimized, and the disturbance of root-soil composite were analyzed by the optimized cutter. In addition, an actual cutter was manufactured and the soil bin experiment was conducted, and it verified the reliability of the simulation results. The simulation results showed that the disturbance of soil-root complex by the optimized vertical spiral cutter can reach 91.41%, the maximum power consumption when cutting soil alone was 0.16kW and the maximum power consumption when cutting the root-soil composite was 0.77kW. The soil bin experiment results showed that the coefficient of stability of the plowing depth was 92.34%, the soil fragmentation rate was 95.00%, and the root removal rate was 95.30%;the maximum torque measured in the case of cutting soil alone was 7.93N·m and it was 6.57% lower than the simulation value; the actual measured maximum torque was 34.84N·m in the case of cutting the root-soil composite, and it was 4.91% lower than the simulation value; the correctness of the design was verified by the close agreement between the experimental and simulation values. The vertical spiral soil loosening and weeding machine met the requirements for soil loosening, weeding, and irrigation operations in Camellia oleifera forest in hilly and mountainous areas.