Polymer　ionic　conductors　have　shown　great　promise　as　iontronic　sensors　for　flexible　wearable　devices　and　intelligent　machines.　A　series　of　exquisitely　designed　hydrogels,　ionogels,　and　ionic　elastomers　have　good　mechanical　properties,　such　as　super　stretchability　and　high　elasticity.　However,　most　gels　tend　to　exhibit　softening　or　linear　mechanoresponsive　behavior　when　subjected　to　stress,　which　is　completely　different　from　the　strain-stiffening　behavior　of　the　biological　tissues.　Therefore,　designing　polymer　ionic　conductors　with　good　mechanical　properties　and　strain-stiffening　ability　remains　a　challenge,　which　is　critical　in　improving　the　reliability　and　durability　of　iontronic　sensing.　Here,　we　propose　a　strong/weak　ionic　interaction　strategy　to　develop　poly(ionic　liquid)　elastomers　(PILEs)　through　the　copolymerization　of　imidazolium　ionic　liquid　monomers　and　acrylate　monomers.　The　design　allows　weak　ionic　interactions　to　impart　softness　to　the　polymer　network,　while　strong　ionic　interactions　stiffen　the　network　during　stretching.　The　resulting　transparent　PILE　possesses　ultrastretchability,　immense　strain　stiffening,　good　elasticity,　high　toughness,　and　puncture　resistance.　The　PILE　also　shows　antibacterial　ability　and　good　adhesion　due　to　high-content　charge　groups　in　the　polymer　network.　These　combined　properties　make　the　PILE　an　excellent　candidate　for　iontronic　sensors,　with　excellent　stability　and　sensitivity　to　temperature　and　strain,　demonstrating　great　potential　in　wearable　devices　and　human-machine　interfaces.　©　2024　American　Chemical　Society