Colorectal cancer has high morbidity and mortality rates; therefore, developing new therapeutic drugs and methods for it is crucial. There is increasing evidence that intestinal flora plays a vital role in maintaining intestinal homeostasis and therefore, in the development of colorectal cancer. As such, therapeutic approaches using probiotics such as Bifidobacterium lactis to regulate intestinal flora are expected to represent a new treatment strategy for colorectal cancer. This article introduces and compares the development status of conventional therapies for colorectal cancer, primarily targeted therapy and immunotherapy, the relationship between intestinal flora and colorectal cancer, and the research and application of Bifidobacterium bifidum in colorectal cancer treatment to provide a reference for its clinical application.