Thermoresponsive hydrogels are promising bioinks for extrusion-based 3D bioprinting due to their injectability and in situ gelation under physiological conditions. However, conventional thermogels often show limited mechanical strength and poor shape fidelity after printing. In this study, a multi-crosslinkable thermogel composed of methacryl glycol chitosan (MGC) and thiolated hyaluronic acid (SHA) was developed. MGC undergoes thermal gelation via hydrophobic interactions, while SHA forms additional covalent networks through disulfide bonding and thiol–ene Michael addition. The resulting MGC/SHA thermogel exhibited improved mechanical properties and structural stability compared to MGC-only thermogels. Time-dependent chemical crosslinking enabled tunable rheological properties and high shape fidelity in cell-laden constructs. These results demonstrate the potential of the MGC/SHA thermogel as an in situ crosslinkable bioink for tissue engineering.