SummaryThe three suspected cases of HSV encephalitis who still survive were reported.Case 1, a 8 months old girl, and case 2 of 8 years 11 months old girl were diagnosed with basis of clinical findings and clinical course, serological demonstration of greater than four‐fold rises in complement fixing antibody and non‐CRN antibody, significant rise in CRN antibody (CRN/non‐CRN) and tests which could rule out other common viral originCase 3 was diagnosed by isolation of virus from C.S.F. obtained at intraventricular puncture and by a significant rise in antibody (CF antibody, non‐CRN and CRN an