TRPM5 is a nonselective monovalent cation channel activated by increases of intracellular Ca2+. It has a distinct expression pattern: expression is detected in chemosensitive tissues from solitary chemosensory cells to the taste receptor cells and in pancreatic β‐cells. The role of TRPM5 has been investigated with the use of knockout mouse models. Trpm5‐/‐ mice have a lack of type II taste perception and show reduced glucose‐induced insulin secretion. Expression levels of TRPM5 are reduced in obese, leptin signaling deficient mice and mutations in TRPM5 have been associated with type II diabetes and metabolic syndrome. In this review we aim to give an overview of the activation, selectivity, modulation and physiological roles of TRPM5. This article is protected by copyright. All rights reserved.