Abstract: In order to analyze the adaptability of the four-leg shock shield fully mechanized coal caving support and the two-leg shock shield coal caving support in steep-inclined extremely thick coal seam fully mechanized caving face. The load characteristics and stability of the supports in steep full-mechanized caving mining face is analyzed with measured data, according to the two supports mining face pressure monitoring in Baojishan Coal Mine. By analysis that, the fully mechanized caving face are influenced by friction caused by roof-slip, gravity of support, impact action of the top coal caving, which causes the tipping and downslide of supports, it becomes more serious when the four-leg shock shield supports are used in this face; and the two-leg can strengthen the working resistance of the supports relatively, and reduce the torque that can cause the downslide of supports, improve the stability and efficiency of supports, thereby it can solve a series of problem as the pressure balance of supports, tipping, downslide, and so on.