The invention discloses a pesticide spraying device for agriculture. The pesticide spraying device comprises a bottom plate. Universal wheels are fixedly connected with the four corners at the bottomof the bottom plate respectively. A trolley handle is fixedly connected with the right side of the top of the bottom plate. A pesticide box is fixedly connected with the middle point of the top of thebottom plate. A put-in pipe is fixedly connected with the right side of the top of the inner wall of the pesticide box. The top of the put-in pipe penetrates through the pesticide box and extends outof the pesticide box. By using the pesticide box, the put-in pipe, a first rolling bearing, a threaded rod, a rotating handle, a threaded sleeve, a telescopic rod, a triangular block, a limiting groove, wheels, a supporting column, a supporting plate, a second rolling bearing, a supporting rotating shaft, a spraying nozzle, a forward and backward motor, a forward and backward rotating shaft, a first bevel gear, a second bevel gear, a water pump and a hose in cooperation, the high spraying efficiency is realized, the spraying angle of the spraying nozzle can be adjusted according to requirements, operation is simple, time and labor are saved, and great convenience is brought to a user.