It is known that the pathogenesis of human cancer involves the accumulation of multiple molecular anomalies. ese molecular changes can be listed as DNA sequence changes (point mutations), loss of heterozygosity, up-regulation/down-regulation of mRNA levels and expressive/functional changes in the gene-encoded ion channels. Ion channels are expressed in almost all living cells and form a pathway for charged ions formed from dissolved salts, including calcium (Ca2+), potassium (K+), sodium (Na+) and chloride (Cl-) ions to pass through the lipid membrane. e non-functional behavior of ion channels in any of its roles, such as regulating cell cycle of proliferating cells, interacting with membrane potential, inhibiting apoptosis, altering intracellular Ca2+ balance and adjusting cell contraction, is thought to cause cancer. In the light of this information, the crucial roles of the involvement of ion channels in the cancer mechanism have been revealed in the last decadeand have a central importance in cancer pathophysiology. Accordingly, the role of ion channels in common types of cancer is presented to readers.