In this research, modified PARSEC airfoil representations are developed and they are investigated by the design exploration of airfoils for the Mars airplane. The existent PARSEC airfoil representation method is useful for the aerodynamic optimization and the knowledge discovery, because the original PARSEC airfoil is parameterized based on the aerodynamic theory. In this method, designer can directly define airfoil's parameters, the leading edge radius, the maximum thickness, the maximum camber, and so on, However, the original PARSEC representation cannot use for not subsonic flow (supersonic flow, low Reynolds number flow), because it was parameterized in consideration of a subsonic wing. To solve the several airfoil design problem, modified representation method is constructed and its design performance is investigated by solving multi-objective design problem. This study employs Genetic Algorithm (GA) for exploration of the multi-objective problem. Flowfield is solved by the structured Navier-Stokes solver with Baldwin-Lomax turbulent model. According to these results, the modified airfoil representation method can solve the design problem under the Martian atmosphere better than the original method.