Abstract: Currently, surgery still remains to be a principal modality of medical treatment for the majority of malignant solid tumors. Clinically, in order to prevent tumor recurrence and metastasis, postoperative systemic chemotherapy or radiotherapy is generally performed to remove residual tumor cells. However, these strategies may give rise to significant side-effects and poor patient compliance. Local drug delivery might increase drug concentration in lesion areas and effectively prevent tumor recurrence at lower doses, which is expected to be a more ideal postoperative treatment. Hydrogels have attracted wide attention due to their good biocompatibility and degradability, which is easy to package multiple therapeutic agents with controllable drug release. This review briefly summarizes the research progress in the recent 5 years of hydrogels for local drug delivery after tumor resection and describes the principles, characteristics and representative research of injectable and sprayable in situ forming hydrogels; and additionally, prospects future applications and challenges to provide reference for the basic research, project approval of new preparation and translational development of hydrogels.