We report a new kind of thermoplastic elastomer using poly(vinyl alcohol) (PVOH) and a high-melting ionic liquid (IL), 1-ethylpyridinium bromide. Wide angle X-ray scattering results indicate that the IL is highly miscible with PVOH for PVOH-rich mixtures (up to 40% by mass of IL) while IL-rich mixtures exhibit diffraction peaks from IL crystals that are precipitated in the amorphous phase of the mixture. Thermal analysis shows that both the melting temperature (T-m) and the glass transition temperature (T-g) of the "as-cast" mixtures decrease noticeably as It content increases, indicating good miscibility of IL with PVOH. Physical aging of the mixtures for I week at room temperature led to the appearance of a secondary endothermic peak at almost constant temperature irrespective of the mixture composition, suggesting the formation of an IL-PVOH complex. FT-IR analysis shows that the O-H stretching vibration band shifts to higher frequency as IL content increases. This result implies that the IL interacts with the hydroxyl groups of PVOH, forming IL-PVOH complexes that act as physical junctions. The tensile modulus decreases significantly as IL content in the mixture increases, indicating that the IL not only promotes the physical association of PVOH but also acts as a plasticizer. The highly elastic behavior of these mixtures suggests a network structure of PVOH in the presence of IL, in which both the crystalline phase of PVOH and IL-PVOH complexes act as physical cross-links that bridge the IL-swollen PVOH amorphous phase. These observations demonstrate that simple mixtures of a polar polymer and a compatible high-melting ionic liquid can yield thermoplastic elastomers with widely tunable thermal and mechanical properties.