Synthetic hydrogels struggle to match the high strength, toughness, and recoverability of biological tissues under periodic mechanical loading. Although the hydrophobic polymer chain of polystyrene (PS) may initially collapse into a nanosphere upon contact with water, it has the ability to be elongated when it is subjected to an external force. To address this challenge, we employ the reversible addition−fragmentation chain transfer (RAFT) method to design a carboxylsubstituted polystyrene (CPS) which can form a covalently cross-linked network with four-armed amino-terminated polyethylene glycol (4-armed-PEG-NH 2 ), and a ductile polyacrylamide network is introduced in order to prepare a double-network (DN) hydrogel. Our results demonstrate that the DN hydrogel exhibits exceptional mechanical properties (0.62 kJ m −2 fracture energy, 2510.89 kJ m −3 toughness, 0.43 MPa strength, and 820% elongation) when a sufficient external force is applied to fracture it. Moreover, when the DN hydrogel is subjected to a 200% strain, it displays superior recoverability (94.5%). This holds a significant potential in enhancing the mechanical performance of synthetic hydrogels and can have wide-ranging applications in fields such as tissue engineering for hydrophobic polymers.