With　the　development　of　alternatives　to　traditional　fossil　energy　and　the　rise　of　wearable　technology,　flexible　energy　storage　devices　have　attracted　great　attention.　In　this　paper,　a　polyaniline/poly(acrylamide-sodium　acrylate　copolymer)　hydrogel　(PASH)　with　high　flexibility　and　excellent　electrochemical　properties　for　flexible　electrodes　is　fabricated　by　freeze-thaw-shrink　treatment　of　a　highly　water-absorptive　hydrogel,　together　with　in-situ　polymerization　of　aniline　at　a　low　aniline　concentration　(0.1　mol　L−1).　The　PASH　exhibits　a　conductivity　of　4.05　S　m−1　and　an　elongation　at　break　of　1245%.　The　freeze-thaw-shrink　treatment　greatly　improves　the　electrochemical　performance　and　stability　of　the　conductive　PASH.　The　area　specific　capacitance　of　PASH　reaches　849　mF　cm−2　and　the　capacitance　maintains　89%　after　1000　galvanostatic　charge–discharge　cycles.　All　the　raw　materials　are　conventional　industrialized　materials　and　no　additional　templating　agent　is　needed　during　the　entire　synthesis　process.　This　study　provides　a　cost-efficient　approach　for　the　fabrication　of　conductive　polymer　hydrogels,　which　has　a　broad　application　prospect　in　flexible　energy　storage　electronic　devices.　©　2020　WILEY-VCH　Verlag　GmbH　&　Co.　KGaA,　Weinheim