Calcium (Ca²⁺)-activated chloride channels play fundamental roles in numerous physiological processes including transepithelial ion/fluid secretion, cardiac and neuronal excitation, sensory transduction, smooth muscle contraction and fertilization, etc. Despite their physiological importance，the molecular identity of CaCC has not fully invested till now. Here the newly discovered CaCCs molecular basis TMEM16A was reviewed in the respects of the identification processes, gene structure and functions, ion channel's electrophysiological characters, related diseases, pharmocoligical functions and other current hot issues in the fields. The developmental trends of this field were discussed.