The utility model discloses a rape field small management machine which comprises a chassis, a lifting hole is formed in the middle of the left side end of the chassis, sliding rails are arranged at the left side end of the chassis in a front-back symmetrical mode, a lifting base is arranged on the sliding rails, a spraying device is arranged at the left side end of the lifting base, and a plurality of nozzles are evenly arranged on the spraying device. A stand column matched with the lifting hole is arranged on the left side of the top end surface of the chassis; a supporting plate B matchedwith the sliding rail is arranged at the top end of the stand column; a motor is arranged at the top end of the supporting plate B, a supporting plate A is arranged at the bottom of the side wall of an inner cavity of the lifting hole, the top end of the supporting plate A is rotationally connected with a lead screw matched with the sliding rail through a bearing seat, the lead screw is rotationally connected to the supporting plate B through a bearing, the lead screw is sleeved with a pushing plate, and the pushing plate is fixedly connected with the lifting seat; the motor drives the lead screw to rotate, so that the push plate is driven to move up and down, the lifting seat is pushed to move up and down along the sliding rail, the height of the spraying device is adjusted, and the requirements of oilseed rapes in different growth stages are met.