The invention provides an aircraft spraying state monitoring device and an aircraft spraying operation area measurement system. The aircraft spraying state monitoring device comprises a spraying state monitoring unit, a global satellite navigation system GNSS, a height measuring unit, an airborne supervisory control unit and an airborne display unit. The airborne display unit is connected with the spraying state monitoring unit, the global satellite navigation system GNSS, the height measuring unit and the airborne supervisory control unit, and is used for displaying spraying state monitoring data collected by the spraying state monitoring unit, the position, velocity, course and flight height data of the aircraft operation, the distance data of a spray lance and the ground plant canopy, and aircraft pesticide application state data corresponding to different time nodes, wherein the position, velocity, course and flight height data of the aircraft operation are collected by the GNSS, and the distance data are collected by the height measuring unit. The aircraft spraying state monitoring device provided by the invention is capable of effectively monitoring the spraying state during aircraft operation.