Abstract: Apoptosis disorders have an important function in the development of gastrointestinal cancer. BNIP3 is a member of the BH3-only subfamily of the bcl-2 family, which contains a BH3 domain and a transmembrane domain, and belongs to the mitochondrial pro-apoptotic proteins. BNIP3 induces cell death via the caspase-independent mitochondrial apoptotic pathway and mediates autophagic cell death. BNIP3 expression is regulated by hypoxia and other factors. BNIP3 expression in tumors exhibits tissue specificity; BNIP3 is highly expressed in some tumors, including breast, lung, and cervical tumors. In pancreatic, gastric, and colorectal cancers, BNIP3 is epigenetically silenced. The absence of BNIP3 in the tumors can cause tumor cells to tolerate hypoxia and may be associated with chemotherapy and radiotherapy resistance. A comprehensive understanding of the spectrum of BNIP3 expression in a various tumors is necessary to use BNIP3 as a marker in clinical applications to treat tumors and as a new target in tumor prognosis.