A coal mine paste filling method mining hydraulic support supporting strength design method comprises the following steps: S1, obtaining basic data of a first rock stratum covering a working face according to a coal measure strata comprehensive histogram; S2, calculating the self-weight stress q of a first rock stratum covering the working surface, namely the cracked roof, according to the following formula q = gamma h; S3, constructing a coal wall, hydraulic support and filling body supporting system model of the paste filling method mining working face; S4, calculating the distribution q(x)of the supporting force from the filling body on the key rock mass of the cracked roof; and S5, mining the hydraulic support supporting strength Pc according to the calculated paste filling method. The coal mine paste filling method mining hydraulic support supporting strength design method adopts a simple technical means, simplifies the difficulty in designing the support strength of the hydraulic support mined by the coal mine paste filling method into theoretical calculation based on a conventional monitoring result, better solves the technical problem of poor filling effect caused by unreasonable design of the support strength of the hydraulic support mined by the coal mine paste filling method, and has the advantages of simplicity, convenience and quickness in operation and low cost.