Abstract: By using FLAC^3D technique,this paper analysed the essential rules of coal and rock movement,and the characteristics of coal deformation and failure modes,and the three dimentional stress in the process of mechanized top-coal caving.The study revealed the mechanical behavior and the movement trend of the hydraulic supports in top-coal caving working face.The results showed conclusion in accordance with the field situations,which is of important theoretical meaning to direct the practice in similar engineering.