Thermoplastic polyurethane (TPU) is attracting attention as an alternative new material for rubber materials that require excellent physical properties. However, TPU has a high affinity for moisture and is vulnerable to a humid environment, so there is a limit to its commercialization. To solve this problem, ethylene vinyl acetate (EVA), which has a low absorption rate and high affinity with other resins, was blended using maleic anhydride (MAH) grafted EVA(EVA-g-MAH) as compatibilizer (TPU/EVA). But this blend has poor mechanical properties compared to the original TPU. In this study, therefore, a surface-modified silica filler by a silane coupling agent was added to the blend to improve mechanical properties. TPU/EVA with surface-modified silica filler (TPU/EVA/Silica) shows a decrease in moisture absorption and improvement in mechanical properties due to the dispersity of silica particles. When the silane coupling agent was added more than 3phr, the degree of dispersion became worse because it behaved like a plasticizer. As a result, mechanical properties decreased, and water absorption increased.