Based on difficult control of movement law of shearer cutting system， simulation analysis was made for cutting coal seam of shearer. Mechanical simulation model of cutting coal seam of shearer drum and cutting section was built to analyze different haulage speeds of shearer. x，y displacement and acceleration of the upper node 26767 of rocker arm were studied. At the same time，vibration characteristics of cutting part in cutting process were analyzed， which laid a foundation for overall controlling dynamic characteristics of shearer cutting unit.