Aiming at the problem of that the power consumption of disc type ditcher is difficult to test, a virtual test platform evaluation disc type ditcher set power consumption method was proposed. Firstly, the dynamics model of disc type ditcher was established. In order to shorten the operation time, the secondary characteristics such as chamfer, fillet and connection were omitted. The boundary conditions and loads were set up. The virtual simulation of power consumption in disc type ditcher was carried out with trenching depths of 400mm and 500mm, forward speeds of 0.8km/h and 1.5km/h, rotation speeds of 180r/min and 220r/min, respectively. The power curve of ditch process showed that at the beginning of soil cutting, power consumption was increased quickly, the reason for which was a great deal of power consumption was needed during the process of soil deformation and broken. After that the power consumption was tended to be stable, for the reason of which was the binding force was tended to be less after the soil particle was destroyed. Then the field power test system was built and the relative errors were 6.88% and 7.73%, respectively, compared with simulation results. The accuracy and feasibility of the proposed method were verified. Finally, totally 18 conditions (three trenching depths, two forward speeds, and three rotating speeds) were selected to carry out the simulation. The results showed that with a certain trenching depth, the disc type ditcher had an increasing linear relationship with forward speed and rotation speed. With a certain ditching depth and forward speed, the lowest power consumption was appeared at rotation speed of 200r/min. Moreover, with a large trenching depth and forward speed, the effect of rotation speed on power consumption was obvious. When the rotary speed was 200r/min，both low and high speeds, disc type ditcher had the lowest power consumption value. According to comparison at rotary speed of 219r/min in different ditching depths and forward speeds, the power consumption at rotary speed of 200r/min was decreased by 8.5kW, 9.6kW and 4.6kW, the results provided a theoretical basis for power consumption measurement of rotary ditcher.