Herpetic gingivostomatitis (HGS) is the predominant manifestation of cutaneomucosal herpes in children with HSV1 primary infection before the age of 3 years. The infection is self limiting and lasts 10 to 14 days. Pain and dysphagia are particularly important during the first week of infection and may necessitate parenteral rehydratation and administration of antalgesics. HGS in the young child causes substantial morbidity leading to hospital and social costs (work stoppage for parents). The clinical course is generally benign with the exception of forms with important extension, eczema, herpeticum Kaposi-Juliusberg pustulosis observed at this age only in children with atopic dermititis. Other severe forms are observed in the neonate and immunodepressed subject, which can also be caused by HSV1. Forms with little or not clinical manifestation predominate and generally go undiagnosed, explaining the asymptomatic viral excretion observed in the saliva or other secretions (ocular, genital secretions). Despite the sterotypic nature of the clinical expression, HGS is still often undiagnosed both by general practitioners and pediatricians. This lack of diagnosis generally has few consequences due to the benign course in a few days, but the infection can have an important psychological and social leading to significant healthcare costs. Moderate and severe forms require medical care. Aciclovir should be prescribed if the diagnosis is made early (3 days) in combination with symptomatic care. Studies of the medical and economic impact of herpetic gingivostomatis should be conducted.