Primary herpetic gingivostomati tis(PHG) is an infection of the oral cavity caused by herpes simplex virus type 1 (HSV-1). It occurs most often in infants and children younger than 6 years of age but can also be seen in adolescents and adults. Patients present with diffuse, erythematous, shiny involvement of the gingiva and the adjacent oral mucosa, with varying degrees of edema and gingival bleeding. In its initial stages, its presence is characterized by discrete, spherical gray vesicles, which may occur on the gingiva, labial and buccal mucosae, soft palate, pharynx, sublingual mucosa, and tongue[7]. This article presents an acute episode of primary herpetic gingivostomatitis in a 13-year-old female patient.