Display omitted •A self-association zwitterionic hydrogel was prepared by simple copolymerization.•The hydrogel had suitable elasticity and electrical excellent ionic conductivity.•The hydrogel enhanced the maturation and functionalization of cardiomyocytes.•The hydrogel promoted electrical signal transfer and cell synchronous contraction.•The hydrogel derived cardiac patches improved the restoration of cardiac function. In recent years, engineered cardiac patch (ECP) with electrical conductivity has been developed for cardiac repair after injury or infarction. However, the application of traditional conductive polymers in ECP is still limited due to their toxicity and difficulty in dispersing and degradation. Herein, a self-association crosslinked conductive zwitterionic hydrogel was developed by simple copolymerization of zwitterionic monomer carboxybetaine methacrylate (CBMA) and a biocompatible monomer hydroxyethyl methacrylate (HEMA). The fabricated p(CBMA-co-HEMA) hydrogel possessed excellent ionic conductivity, suitable compressive and stretchable properties, self-healing and mechanical sensory capability. In vitro, the zwitterionic hydrogel significantly enhanced the functionalization of the cardiomyocytes, resulting in excellent synchronous contraction by increasing the expression of cardiac-related factor α-actinin and transmission electrical signal-relevant Connexin-43 (CX-43). In vivo, the hydrogel-derived functional patch effectively promoted the transmission of electrophysiological signals, improved revascularization in infarcted area and then remarkably restored the cardiac function. These data indicated that our developed conductive zwitterionic hydrogel has good promise in repairing myocardial tissue injury.