The invention discloses a use method of a plant detection device for atmospheric pollution. A base is arranged at the bottom of a device body, a control box is mounted at the top of the base, a detection box is mounted at the top of the control box, a water tank is arranged at the bottom in the detection box, support plates are mounted on two sides of the top of the water tank, first electric pushrods are mounted at top ends of the support plates, a planting plate is mounted at the tops of the first electric push rods, second electric push rods are mounted at top ends of two sides in the detection box, a top plate is mounted at the top ends of the second electric push rods, and castors are mounted at the bottom of the base. The detection box is hinged with the second electric push rods and the top plate, the structure is simple, rotation is flexible, opening and closing of the top plate are facilitated, the angle of a solar cell panel can be adjusted conveniently, the energy utilization rate can be increased, the work cost of the device body can be reduced, atmospheric pollution detection plants can be protected in severe weather such as rainstorm, extra management of workers is not required, and the labor intensity of the workers is reduced.