Rotary tillage operation generally has problems such as shallow tillage depth (8-15cm), low depth of mixed burying of straw, and high power consumption. Increasing the tilling depth by increasing the turning radius of the rotary tiller has problems such as huge mechanism and increased power consumption. In this paper, a deep rotary machine was designed, which could still achieve deep operation (tillage depth of 20cm) when the blade turning radius was reduced. Through the method of simulation and experiment, the article compared the operating performance of the deep-rotating machine and the common tool with increasing rotary radius. The result shown the advantages of the deep-rotating machine in the index of tillage depth and power consumption; the parameter pair of the deep-rotating machine was clarified. For the impact of job performance, the methods of variance analysis and response surface analysis were adopted to explore the relationship between parameters and indicators and fitted mathematical models. Field experiments were carried out and compared with the simulation analysis results. The errors between field test results and simulation analysis were 8.2%, 3.5% and 4.2% in power consumption, soil fragmentation rate and straw coverage rate. The average error in soil vertical displacement was 15.2%, and the longitudinal displacement error was 16.9%. The average error in the vertical distribution of straw is 15.7%.