In this paper, establishment of design methods for competitive swimwear using numerical analysis was investigated. Now, FINA's regulations permit to make competition swimwear by the fabric material. The fabric materials have two mechanical properties. The one is nonlinear elasticity which is regarded as hyperelasticity like rubber. Another is anisotropic that depend on the directions of two fiber families. Therefore, an anisotoropic hyperelastic model was proposed for the mechanical behavior of swimwear materials and the applicability of the FEM method to the swimwear materials was shown. The properties of swimwear fabrics were estimated by uniaxial tensile tests. From the test results, the material parameters for anisotropic hyperelasticity were determined by the nonlinear least square methods. The simulated results calculated by FEM were also shown to investigate the applicability of numerical simulation to the design of competition swimwear.