Abstract: The equivalent mining height theory is an important method to analyze the control effect of rock movement in filling mining.By analyzing the numerical value of each component of equivalent mining height in solid filling mining of gangue, it is concluded that reducing the compressibility of gangue filling material is an effective means to reduce equivalent mining height, and obtaining the optimal particle size grading of gangue is the key.The gangue with grain size below 100 mm is divided into five grades (100-75 mm, 75-50 mm, 50-25 mm, 25-13 mm and 13-0 mm).Based on the continuous gradation theory-Talbal Theory, five groups of gradation schemes with different grain size are designed according to the gradation index n=0.3-0.7.Under the stress condition of overburden rock at a depth of 400 m, the compression test of gangue solid filling material with a diameter of 380 mm and a height of 240 mm is carried out.The results show that the strain increases with the increase of axial stress, the rate of strain increase decreases with the increase of axial stress, and the scheme with grading index n=0.5 has the minimum strain.According to the strain-stress fitting relation, the expression of minimum equivalent mining height is obtained, which provides a quantitative basis for analyzing the control effect of rock strata movement in gangue solid filling mining.