ANO1, anoctamin 1(also known as TMEM16A), is the molecular basis of calcium-activated chloride channels with ten transmembrane segments which are widely expressed in mammalian cells, including epithelial cells, vascular smooth muscle tissues, electro-excitatory cells, and some tumor cells. These proteins are widely expressed in mammalian cells, including epithelial cells, vascular smooth muscle tissues, electro-excitatory cells, and some tumor cells. To date, multiple studies have shown that many natural and synthetic compounds have regulatory effects on ANO1. Therefore, ANO1 could be a potential new drug target for the treatment of cancer, pain, diarrhea, hypertension, and asthma. Here we review the structure of ANO1 and its involvement in cancer, pain, diarrhea, hypertension, and asthma.