Background: Despite advances in antiviral therapy over the past 2 decades, herpes simplex encephalitis (HSE) remains a serious illness with significant risk of morbidity and death. HSE is the most common cause of sporadic viral encephalitis, with a predilection for the temporal lobes and a range of clinical presentations, from aseptic meningitis and fever to a severe rapidly progressive form involving altered consciousness. Clinical features of HSE include fever with mental status changes (depressed level of consciousness, confusion, disorientation, personality changes) sometimes with seizures (focal or generalized), dysphagia, or other focal neurological signs. Symptoms vary in intensity early in the disease, but tend to progress rapidly. CT and MRI can play an important role in determining the diagnosis and extent of the disease. Case Report: This case report refers to a 17-year-old girl, previously diagnosed with herpes encephalitis, and presents the outcome of rehabilitation on the patient's mental state during a 7-year follow-up period. Conclusions: The prognosis for patients with HSE has been dramatically improved by the availability of specific antiviral therapy; sequelae in surviving patients may include severe neurological deficits, seizures, and/or neuropsychological dysfunctions that greatly impair quality of life. To improve the prognosis for patients with HSE, acyclovir treatment should be initiated as soon as HSE is suspected. After discharge, rehabilitation should be provided, in the effort to improve the patient's self-reliance in everyday life.