Abstract: Taking 1102 gangue filling face of Tingnan Coal Mine as the research object, theoretical analysis, numerical simulation, laboratory test and field measurement were used to study the process of gangue compression and the law of strata subsidence. The results show that: after 2 MPa compaction, the bulk gangue is compressed by 27.05 % to become gangue filling body, the mechanical compression process of gangue filling body in fillable space and the compression rate (the ratio of compression amount in each stage to fillable space height) are: skeleton adjustment（7.42%）, slow compression (accounting for 5.39%); the equivalent mining height of mechanical compression is the product of the fillable space height and the second-stage fillable compression rate of gangue filling body. The equivalent mining height of gangue filling body in 1102 working face in skeleton adjustment and slow compression is 0.94 m and 1.10 m respectively; the surface subsidence curves of the main section of 1102 working face in strike and inclination are all in the shape of “bowl”. During the process from skeleton adjustment to slow compression, the surface deformation curve changed little, and the final maximum subsidence was 39 mm and 41 mm, respectively.