Conductive hydrogels have attached considerable attention due to their good stretchability,excellent conductivity when they are applied in soft electronics.However,to fabricate a flexible hydrogel sensor with excellent toughness and good self-healing properties remains a challenge.In this work,we assembled a dual physical-crosslinking(DPC)ionic conductive polyacrylamide/carrageenan double-network(DN)hydrogel.This hydrogel has excellent fracture tensile stress and toughness,and demonstrates rapid self-recovery and self-healing ability due to the unique dual physical-crosslinking structures.Besides,the hydrogel is highly conductive by adding some conductive ions.As a result,the hydrogel-based sensor can stably detect human motions and physiological signals.The work provides novel ideas for the development of flexible sensing devices.