Cancer treatment remains a stuffy problem, which makes the “unconventional” treatment method become the research hotspot in the 21th century. Bacteriolytic therapy of tumor is mainly based on the stimulation of innate immunity and the targeting colonization of some bacteria in solid tumors. Gene modification of the bacteria with tumor-targeting expressing proteins or gene deletion can increase their tumor targeting ability and biocompatibility. The bacteria equipped with cytotoxic proteins and immune factors can efficiently restrain tumor growth. By the virtue of nanomaterial developments, rapid progresses have been made in researches on the treatment of tumors by combining bacteria with nanotechnology and the nanometer properties of bacterial products. Besides, tumor targeting bacteria can effectively reduce the side effects of clinical treatments, such as chemotherapy, radiotherapy, and immunotherapy, and enhance their anti-tumor effects. Exploring the tumor targeting ability, immune anti-tumor property of bacteria, as well as auxiliary for clinical treatment will provide a new idea and approach for human to conquer cancer.