Epstein-Barr virus (EBV) has been detected in a wide spectrum of tumors. This study investigates the detection rate of EBV-DNA by Southern blot hybridization analysis (SOBH) and polymerase chain reaction (PCR) in different tissues from persons without apparent EBV-related diseases. Of 20 tonsillectomy specimens studied, SOBH indicated positivity for EBV-DNA in 1 case, and PCR indicated positivity in 10. In autopsies performed on patients with no apparent evidence of EBV-related diseases, the viral DNA was only detected by PCR in the following: parotid gland (7/15), submandibular gland (8/20), nasopharynx (8/10), tonsil (8/10), larynx (5/6), lung (5/9), cervical lymph node (7/10), mediastinal lymph node (7/10), abdominal lymph node (4/10), spleen (6/10), thyroid (5/10), liver (1/10), pancreas (1/4), kidney (4/10), uterine cervix (1/4), ovary (1/5) and testis (1/3). These results provide a baseline for interpreting the role of EBV in carcinogenesis.