Cancer immunotherapy, which use the own immune system to attack tumors, are increasingly popular treatments. But, due to the tumor immunosuppressive microenvironment, the antigen presentation in the tumor is limited. Recently, a growing number of people use bacteria to stimulate the body’s immunity for tumor treatment due to bacteria themselves have a variety of elements that activate Toll-like receptors. Here, we discuss the use of motility of flagellate bacteria to transport antigens to the tumor periphery to activate peritumoral dendritic cells to enhance the effect of in situ tumor vaccines.