Abstract: Based on the hypersonic entry in the entry-descending-landing procedure,the three-dimensional Navier-Stokes equations are solved by a parallel code to analyze the flow field structures, the aerodynamic characteristics and their variation patterns of the Mars Science Laboratory entering the Martian atmosphere with and without the chemical reaction models. The analysis shows that a large number of CO₂ is dissociated behind the shock and much energy is consumed, with the chemical non-equilibrium effect, the shock layer is strongly compressed. The comparisons between the real gas and the perfect gas show that the vortex in the wake flow is reduced, the positions of the separation lines and the singularity are distinctly different; under the chemical non-equilibrium condition, the lift coefficient almost keeps the same, the drag coefficient increases, the lift-to-drag ratio and the pitch moment are smaller than those of the perfect gas.