Light-stimulus-responsive therapies have been recognized as a promising strategy for the efficient and safe treatment of oral squamous cell carcinoma (OSCC). Hydrogels have emerged as a promising multifunctional platform combining localized drug delivery and sustained drug release with multimodal properties for combined OSCC therapy. However, inaccurate drug release and limited light-absorption efficiency have hindered their on-demand chemo-photothermal applications. To tackle these problems, an injectable and near-infrared (NIR) light-responsive hybrid system was developed by incorporating light-responsive mesoporous silica nanoparticles (MSNs) as doxorubicin (DOX) carriers into the IR820/methylcellulose hydrogel networks for chemophotothermal therapy. Under NIR radiation, the incorporated IR820, a new green cyanine dye, was excited to induce photothermal effects against tumor cells. Meanwhile, MSNs achieved self-degradation-controlled DOX release via the cleavage of diselenide bonds induced by reactive oxygen species. Through the combination of chemotherapy and phototherapy, a long-lasting synergistic anti-tumor effect was achieved in vitro and in vivo with less toxicity. These findings demonstrate the potential of light-responsive hydrogels as a multifunctional platform for accurate synergistic chemophotothermal treatment of OSCC.