Cancer is a common cause of mortality in the world. For cancer treatment modalities such as chemotherapy, photothermal therapy and immunotherapy, the concentration of therapeutic agents in tumor tissue is the key factor which determines therapeutic efficiency. In view of this, developing targeted drug delivery systems are of great significance in selectively delivering drugs to tumor regions. Various types of nanomaterials have been widely used as drug carriers. However, the low tumor-targeting ability of nanomaterials limits their clinical application. It is difficult for nanomaterials to penetrate the tumor tissue through passive diffusion due to the elevated tumoral interstitial fluid pressure. As a biological carrier, bacteria can specifically colonize and proliferate inside tumors and inhibit tumor growth, making it an ideal candidate as delivery vehicles. In addition, synthetic biology techniques have been applied to enable bacteria to controllably express various functional proteins and achieve targeted delivery of therapeutic agents. Nanobiohybrids constructed by the combination of bacteria and nanomaterials have an abundance of advantages, including tumor targeting ability, genetic modifiability, programmed product synthesis, and multimodal therapy. Nowadays, many different types of bacteria-based nanobiohybrids have been used in multiple targeted tumor therapies. In this review, firstly we summarized the development of nanomaterial-mediated cancer therapy. The mechanism and advantages of the bacteria in tumor therapy are described. Especially, we will focus on introducing different therapeutic strategies of nanobiohybrid systems which combine bacteria with nanomaterials in cancer therapy. It is demonstrated that the bacteria-based nanobiohybrids have the potential to provide a targeted and effective approach for cancer treatment.