Ionic conductors, such as hydrogels, ionogels, and eutectogels, have attained considerable research interest in various advanced application scenarios. However, such ionic conductors still suffer from the restriction of inherent liquid compositions, which may leak or evaporate. Herein, inspired by the control strategy of desertification caused by soil erosion, a novel internal-external dual enhancement design strategy, i.e., increasing the interaction between the filler itself and its matrix, is proposed to firmly embed the deep eutectic solvent (DES) into polyurethane (PU) to prevent liquid leakage, such that the prepared ionic conductive elastomers (PU-DESs) are quasi-solid. The PU-DESs exhibit marvelous versatility including high stretchability, tensile strength, toughness, self-healing efficiency, antibacterial ability, ionic conductivity, and excellent freezing tolerance. More intriguingly, benefiting from their quasi-solid feature, PU-DESs are endowed with long-term environmental stability. Thanks to these superb versatile features, PU-DESs are further successfully applied in the wearable sensor and triboelectric nanogenerator (TENG) for monitoring human motions and converting mechanical energy into electrical energy, breaking away from the limitations of previous most soft iontronics such as liquid leakage or evaporation and weak mechanical strength. Hence, this study establishes an effective material design strategy for various soft iontronics demanding environmental stability and durability.