PCR has been commonly used for genomic viral diagnosis for its sensitivity and accuracy. It showed a higher sensitivity when compared to virus isolation in tissue culture and also in antigenemia detection. Definitely, DNA samples are critical factor in PCR validity. Out of 167 serum samples subjected to this study and extracted by Wizard® DNA purification mini kit, 47 samples (28.1%) were positive PCR. While, 21 samples (12.6%) only out of the same population study (167) were positive PCR for EBV DNA in native serum samples (without DNA extraction). This result was confirmed the importance of DNA extraction from serum samples for detection of EBV which, subsequently lead to more sensitive diagnostic tool of an ongoing EBV infection.