Abstract: Olfactory receptors (ORs) are transmembrane proteins mainly distributed in olfactory sensory neurons of the nasal epithelium, mediating the transmission of real-time sensory signals to the brain to produce smell. Recent studies have reported that ORs can also be expressed in tissues or organs outside the nasal cavity, and are closely related to a variety of biological processes, such as sperm chemotaxis, wound healing, glycolipid metabolism and intestinal secretion. In addition, ORs are closely related to a variety of malignant tumors such as prostate cancer, breast cancer and colorectal cancer, and may affect the occurrence and development of tumors by regulating cell proliferation, apoptosis, migration and invasion. This review provides an overview of the effects of ectopic ORs on the function of various human tissues and organs and assesses their potential value as drug targets for the treatment of human diseases.