Introduction Central nervous system (CNS) viral infections are a serious problem requiring accurate diagnosis and treatment. Human herpesviruses (HHVs) are an important cause of these infections. Recent research has focused on new diagnostic methods allowing accurate and rapid identification of viral infections because there are still diagnostic difficulties for these infections. This study was done to determine the etiologic role of human herpes viruses and to obtain information that will contribute to the diagnostic algorithm in suspected cases of viral encephalitis or aseptic meningitis. Materials and Methods In our study, herpes simplex virus (HSV)-1, HSV-2, varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), and HHV-6 DNA was detected in the cerebrospinal fluid (CSF) by multiplex polymerase chain reaction (PCR) and virus-specific immunoglobulin G (IgG) antibodies in CSF and serum by EIA in pediatric encephalitis/meningitis cases. Results HSV-1 and VZV were detected in 5 and 3.3% of aseptic meningitis cases, respectively, but no encephalitis cases. Other viruses were not identified as etiologic agents. The seroprevalences were determined as 72.4, 34.3, 81.9, 93.3, 88.6, and 80.9%, respectively for HSV-1, HSV-2, VZV, CMV, EBV, and HHV-6. The performance of specific IgG CSF/serum antibody index (AI) was not satisfactory. Conclusion Our study indicates that the multiplex PCR method is the most suitable for the diagnosis of CNS infections caused by HHVs. However, due to the high cost of the PCR method, the positive results of the specific AI may be significant, but the negative results are unreliable, especially in limited health care facilities.