To explore N-2-enhanced coalbed methane (N-2-ECBM) recovery with different gas contents, six specimens (R-o,R-ran = 0.42-3.23%) in Shanxi Province, China, were selected to physically simulate N-2-ECBM recovery via laboratory testing. The volume shrinkage characteristics and desorption percentage (DP) evolution patterns of coal were studied during N-2 injection and sealing (N-2-IS) and desorption with stepwise depressurization (DSD). The results show that a linear relationship exists between the volume deformation and coal adsorption/desorption gas. The volume strain of specimens with low elastic modulus (E-s) <3500 increases greatly with increasing gas content, which leads to a decrease in reservoir permeability. However, CH4 desorption will also substantially increase the permeability during N-2-IS. After long-term gas recovery, the mechanical properties of depleted wells will be reduced, and gas production will resume after N-2-IS. During the N-2-IS, the DP of samples with low gas content decreases with increasing micropore volume, and reabsorption appears in high-rank coal. The induced strain rate decreases with increasing micropore volume and E-s, increases with increasing macropore volume, and increases at first and then decreases with increasing coal rank. During the DSD process, there is no significant difference in DP at each stage, indicating that is the key to stable gas production in N-2-ECBM recovery. Finally, the cumulative DP was gradually increased by the influence of reservoir gas content. It is revealed that high-pressure N-2-IS can effectively improve gas production for reservoirs with congenital low pressure but well-developed permeability or depleted wells that have experienced a large amount of gas production. For low-permeability reservoirs, high-pressure nitrogen pressure fracturing can be performed first to increase permeability, followed by the N-2 sealing stage.