Plasma cell gingivitis is a rare condition characterized by diffuse and massive infiltration of plasma cells into the sub-epithelial connective tissue.It is considered as a hypersensitive reaction to an allergen, the etiology of this bizarre condition is still not properly understood.Plasma cell gingivitis is a rare benign condition of the gingiva characterized by well demarcated erythematous and oedematous gingiva often extending to the mucogingival junction. Here we are presenting a case of plasma cell gingivitis in a partially edentulous arch.The condition was diagnosed based on clinical and histopathologic findings. Early diagnosis is essential as plasma cell gingivitis has similar pathologic changes seen clinically as in leukaemia, HIV infection, discoid lupus erythematosus, atrophic lichen planus, desquamative gingivitis, or cicatrical pemphigoid which must be differentiated through hematologic and serologic testing.