The utility model belongs to agricultural equipment and relates to a soil preparation and pesticide spraying combined operation machine. The soil preparation and pesticide spraying combined operation machine comprises a traction frame, a pesticide spraying device, a machine frame, a pesticide box, a disc harrow group, a lifting oil cylinder, a conveying wheel, a soil crushing roller, a soil crushing and compacting roller frame, a supporting arm and a compacting roller, wherein the pesticide box is mounted on the machine frame; the pesticide spraying device is arranged in the front of the machine frame; the disc harrow group, the soil crushing roller and the compacting roller are mounted below the machine frame; the soil crushing roller and the compacting roller are mounted on the soil crushing and compacting roller frame through a bearing; and one end of the supporting arm is fixedly connected with the machine frame and the other end of the supporting arm is hinged with the crushing and compacting roller frame. When the machine works, the pesticide spraying device sprays pesticide on the surface of the ground, the disc harrow group turns and loosens soil and mixes the pesticide and the soil, the soil crushing roller crushes the soil and further mixes the soil with the pesticide, and the compacting roller compacts the soil. By adoption of the soil preparation and pesticide spraying combined operation machine, the pesticide and the soil can be mixed timely, volatilization loss of the pesticide is avoided, and the productivity of the machine is improved.