Owing to the many unknown parameters and complex overlying stratums structure evolution, the back analysis of the dynamic deformation is becoming a typical complex nonlinear optimization problem.In order to overcome the low efficiency of the conventional inversion method in multi-parameters back analysis,firstly, using the strata control theory to analyze the dynamic structure evolution of overlying stratums, and choosing the global search optimization algorithm-genetic algorithm,besides combining the implicit nonlinear relationship between supporting resistance and the multi parameters of the overlying rock to find the minimum between field measured value and numerical calculation values, and the unknown lithologic parameters were determined when the minimum was achieved.Among these unknown parameters, including the rock mass density, mechanical parameters—elasticity modulus and poisson ratio, and strength parameters—cohesion and internal friction angle.Lastly, choosing the No.8206 working face in Qingciyao coal mine as the testing site,the hard stratum fracture overlying which always lead to the rapidly increase of supports resistance, and combining the hydraulic supporting resistance value variation with time, and using the algorithm to acquire the optimal parameters and instability rules of the main roof, and the simulation results show a good agreement with the measured results.Then, in this study, using the optimal numerical model can well analyze the fracture characteristic of the overlying stratums and the variation of the hydraulic supports with the different advance distances.