Abstract: The coal molecule model and quantum dynamics model of absorption model for coal and CH₄ were established by taking the radius of Van Der Waals force as the boundary condition. The coal macromolecular skeleton model and the absorption model structure of coal and CH₄ were optimized and obtained multiple adsorption equilibrium geometry and configuration of stable equilibrium adsorption with the DFT method and 6-311G++ basis. The changes of coal molecule on the absorption position, potential energy curve of adsorption and the bond length and bond angle of CH₄ were studied by analyzing the Mulliken atomic charges of coal macromolecular skeleton model.