In order to study the dynamic model of laser grader in paddy field, improve the accuracy of control algorithm and optimize the design of mechanical structure, a dynamic measurement method of position and attitude parameters of grader based on monocular highspeed camera was proposed. Direct linear transformation (DLT) was used to establish the corresponding equations between monocular camera and local coordinate system, monocular camera and flat shovel platform respectively, and indirectly solve the transformation relationship between the two coordinate systems on flat shovel by Gauss-Newton iteration method, so as to realize the measurement of spatial position and attitude angle of flat shovel. Experiments were carried out with a monocular highspeed camera, and the data were compared with that of the attitude and heading reference system (AHRS) sensor. The experimental results showed that this method can measure the position and attitude parameters of the flat shovel. Compared with the AHRS sensor, the average absolute error of attitude angle was 0.687° and the standard deviation was 0.543°. The maximum absolute error occurred when the flat shovel was moved to a limit position of 3.76s, which was -1.92°. The measured position of the center of mass in the X, Y and Z axes was in accordance with the actual movement of the flat shovel. The motion condition provided a method for the simulation and verification of the dynamic model of the flat shovel.