The invention relates to a coulter type mixing machine which comprises a cylindrical barrel, a speed reducing motor, a spindle, a group of coulters and multiple groups of fly cutter devices. The speed reducing motor is fixedly installed on a left wallboard, and a bearing block is fixedly installed on a right wallboard. Packing boxes and packing box pressing covers are arranged in the middle of the ends of both the left wallboard and the right wallboard connected with the barrel and are assembled together. One end of the spindle is connected to the speed reducing motor, the other end of the spindle is connected to the bearing block, and the adjacent coulters of the group of coulters are staggered in the axial direction of the spindle on the spindle located in the barrel. All the coulters are perpendicular to the axis of the spindle. Each fly cutter device comprises a fly cutter blade and a fly cutter motor, the fly cutter blade is connected to a rotating shaft of the fly cutter motor and arranged in the barrel, and the fly cutter motor is positioned on the outer portion of the barrel. The top of the barrel is provided with a feeding port, and the bottom of the barrel is provided with a discharging port. The mixing machine is quick in mixing speed, low in energy consumption and high in mixing accuracy.