The 3-D hypersonic chemical non-equilibrium flow over reentry capsule is simulated numerically. The full Navier-Stokes equations are taken as the governing equations. The chemical non-equilibrium air model is considered and seven species are N₂、O₂、NO、N、O、NO⁺、e^-. Using NND Scheme for shock capture and implicit scheme to deal with the chemical source terms, the numerical results are in agreement compared with the experimental data. The perfect gas results are given for analysis of the real gas effect.