Human herpes virus-6 (HHV-6) is a ubiquitous virus, but one that can induce various neurological diseases. Recently, several seizures have been reported as new HHV-6-associated diseases based on virological analysis. Neonates who are perinatally infected with HHV-6 can develop afebrile seizures, which are considered to be exanthem subitum (ES) in the neonatal period. Infants with ES also tend to develop atypical febrile seizures. After primary infection, HHV-6 commonly establishes latency in the central nervous system (CNS) and sometimes reactivates in the hippocampus, causing limbic encephalitis and temporal lobe epilepsy. These HHV-6-associated CNS diseases due to virus reactivation can occur in both immunocompromised and immunocompetent hosts. This article summarizes HHV-6-associated seizures during childhood.