Plant protection machine

A vehicle body of the plant protection machine comprises two supporting beams extending in the advancing direction of the vehicle body, the two ends of each supporting beam are rotationally connected with steering shafts, and the bottom ends of the steering shafts are fixedly connected with wheels; a plurality of cross beams are connected between the two supporting beams, the connecting positions of the cross beams and the cross beams can be adjusted so that the wheel distance between the wheels connected with the two supporting beams can be changed, air bag assemblies are connected between the wheels and the supporting beams, and the distance can be adjusted through expansion and contraction of the air bag assemblies so that the ground clearance of the mounting frame can be changed. The telescopic end of the air bag assembly is movably connected with the steering shaft, and the air bag assembly is connected with an inflation piece and can be expanded and contracted through the inflation piece. The wheel can