The invention discloses a pesticide spraying device, which comprises a vehicle body, a box body, a storage box and two windproof devices, wherein a power supply is arranged in the box body; the two windproof devices are respectively arranged at two sides of the storage box; the storage box and the box body are arranged above the bottom plate of the vehicle body; wheels are arranged below the vehicle body, a pesticide box is arranged in the storage box, a pesticide adding port of the pesticide box is arranged at the top of the storage box, one side of the pesticide box is provided with a high-pressure water pump, the high-pressure water pump is communicated with a first water pipe, a second water pipe and a third water pipe through a four-way joint, the other side of the high-pressure waterpump is communicated with the pesticide box through a pipeline, the first water pipe is connected with the windproof device on one side, and the second water pipe is connected with the windproof device on the other side. Through arranging the windproof devices, by pulling or loosening the handle, a folding cover is put down and folded to match with the crops with different heights, so that the windproof effect is achieved, and the external wind force is prevented from blowing the pesticide into the air, which influences the environment.