Viral encephalitis refers to acute inflammatory process of brain parenchyma caused by viral agents. Viruses are known to be the most common infectious agents associated with acute encephalitis. Acute neurologic manifestations in viral encephalitis are diverse, including fever, headache, abnormal behaviors, altered consciousness, seizure, and focal or multifocal neurological deficits. A diagnosis of viral encephalitis can be challenging. Real-time polymerase chain reaction test of cerebrospinal fluid is useful in establishing immediate diagnosis and prognosis of the disease. Prognosis differs from the type of viral agent. Prompt diagnosis and management include antiviral treatment and control of elevated intracranial pressure.