Cholesteatoma is a cystic non-neoplastic lesion of a temporal bone that shows hyperproliferation of keratinocytes and abnormally heavy production of keratin in the tympanic cavity with the influence of chronic inflammation. There are crucial complications, bone resorption and infection which make the cholesteatoma aggressive and recurrent. However, the pathogenesis of cholesteatoma is unclear and there are several theories of the pathogenesis but no single theory can explain whole cases of it. The only infallible treatment of cholesteatoma is a surgical intervention. The main objective of this thesis is to give a methodical review of the recent literatures concerning cholesteatoma that collect the traditionally well-known facts together with the latest news focusing especially on the molecular biological aspect of cholesteatoma.