Abstract: The water-rock interaction similar material models were employed to simulate the stress variation, cyclic breaking and the cracks formation and distribution status of the overlying strata with different loading conditions,rock properties and mining process. It was found that the fractal dimension of cracks varied with mining advancing. The evolvement laws of crack network with mining advancing and different mining advancing footage were obtained. Ac- cording to the distribution of mining fractures,the fractal seepage formula of fractured rock mass was derived,and the evolution law of the correlation of the permeability coefficient with the mining process and fracture expansion and the corresponding theoretical formula were obtained. On this basis,by using large-scale similar material physical model test,through the borehole television imaging of the physical model of fracture network of overlying strata under the in- fluence of mining,the distribution of mining fracture was obtained,and the permeability coefficient of model test medi- um with fracture network was calculated by using the derived permeability coefficient correlation evolution theoretical formula. At the same time,the correctness of the theoretical model of permeability coefficient was verified by the bore- hole water injection test. By establishing the relationship between the fractal dimension with the mining length in differ- ent horizontal and vertical zones,it demonstrates that the fractal dimension in horizontal and vertical zones have a self- similar characteristic,and the spatial distribution of mining induced cracks may be saddle shaped,the horizontal zone H3 and H6 have a relative low fractal dimension and H1 ,H4 and H7 ,oppositely have a relative high fractal dimension. At the meanwhile, the fractal dimension reduces with the increase of the caving height, at a rate of 4． 32% to 11． 40% . In the transition zone between the fractured zone and sinking zone, on the contrary, has an increase of 3． 47% ,taking the caving zone as the reference standard. The permeability distribution of mining induced cracks may be “V” shaped in horizontal direction,with a relative low permeability in the middle zone and relative high at the ends. The permeability de-crease gradually with the increase of vertical height and the permeability increase dramatic- ally due to the separation fractures at the transition region of fractured zone and bending zone.