Based on fully mechanized caving faces abutment pressure without quantitative description problem, large mining height fully mechanized caving faces limitation balance area coal body was taken as study object, fully mechanized caving faces forward coal body mechanical model under advanced abutment pressure was set up, advanced abutment pressure was studied by the elastoplastic limit equilibrium theory. Using  FLAC3D numerical simulation software, working face advanced abutment pressure evolution law was simulated and analyzed, simulation analysis abutment pressure value approached theoretical analysis results, which provided a theoretical basis for r advanced abutment pressure distribution law calculation under similar conditions.