There is a bidirectional association between tumor-associated macrophage (TAM) and colorectal cancer. Small molecular substances metabolized by colorectal cancer affect the reprogramming of TAM, and TAM in turn regulates the biological behavior of colorectal cancer cells by secreting small molecular substances, and promotes the progression of colorectal cancer. In addition, gut microbiota metabolites are closely related to TAM reprogramming, and intestinal flora imbalance leads to gut barrier damage, favoring bacterial translocation and causing chronic tumorigenic inflammation. Studying the reprogramming mechanism affecting TAM and its relationship with the occurrence and development of colorectal cancer may provide new ideas for the study of immunotherapy in patients with colorectal cancer. This article reviews the research progress of TAM in patients with colorectal cancer, aims to provide a reference for clinical research.