Periodontitis is one of the most common and public health problems worldwide. It is a multifactorial chronic inflammatory disease involving a complex interaction between various etiological factors, host responses, and environmental factors. Risk factors have still been under investigation. Many studies emphasize the possible bacterial etiology and host responses. Entamoeba gingivalis, is a protozoon that resides in the oral cavity of individuals. Many studies have reported that infection rates of this protozoa was higher in patients with periodontitis compared to healthy controls. However, the role of this protozoon in the development of periodontal disease remains controversial. Therefore, in this review, it is aimed to compile the literature data on E. gingivalis whose pathogenicity is yet to be determined.