Abstract: In view of the influence of the coal seam thickness on rock burst in coal mine, the distribution laws of vertical stress and elastic strain energy under the condition of different coal seam thickness are analyzed by numerical simulation method. The results show that the vertical stress and elastic strain energy increases greatly with the decrease of thickness of coal seam in partial transformation area. When the working face moves to the position coal seam thickness variation, the stress value is 1.37 times of that before the coal seam is excavated. At the same time, the elastic strain energy is 2 times of that before the coal seam is excavated.