Plasma cell gingivitis is a rare, benign inflammatory condition of unknown aetiology. It is said to be a type 4 hypersensitivity reaction to the irritant. It is also known as atypical gingivitis, plasmacytoma of gingiva, and plasma cell gingivostomatits. It requires histological and haematological investigations to confirm the diagnosis. Keywords: Plasma cell gingivitis, atypical gingivitis