Mucin13 (MUC13), a high-molecular-weight transmembrane glycoprotein, is mainly expressed in the epithelial cells of gastrointestinal and respiratory tract and provides protection and lubrication for mucous epithelium. MUC13 is involved in many pathological processes via multiple signaling pathways, such as promoting cell proliferation and metastasis, inhibiting cell apoptosis, reducing cell adhesion and so on. MUC13 not only takes part in the regulation of inflammation, but also plays an important role in the development of tumors. The role of MUC13 in tumors is attracting more and more attention, and it is expected to be a target for early diagnosis and therapy of tumors.