The Epstein – Barr virus is a member of the gamma-herpes viruses (HHV-4). It is a linear 184,000 base pair double stranded DNA virus. It was the first oncogenic virus to be discovered (1). Infection by this virus can show signs of a slight viral infection or it can be present as Infectious Mononucleosis. The most common target cells for the Epstein-Barr virus are the B lymphocytes and the nasopharyngeal epithelial cells. The Epstein-Barr virus massively infects the human population and sero-epidemiological studies show that 90% of adults have been infected by this virus (2). Latently infected B lymphocytes express abundantly (104-105 copies), among other genes, a short non- polyadenylated chain of RNA that does not transduce to a protein, consisting of two fragments known as EBER 1 and EBER 2. The expression of EBER (Epstein-Barr virus encoded RNAs) is nuclear. Although the function of EBER is unknown, it is believed that it may play a role in virus-produced oncogenesis (3). There are numerous human tumors associated with EBV. These range from non-differentiated nasopharyngeal carcinoma to African Burkitt’s lymphoma, Hodgkin’s disease mixed cellularity, some B, T and NK lymphomas, as well as in lymphoproliferative processes associated with immunodeficiency(4). The in situ hybridization technique offers an important advantage over immunohistochemistry, as it virtually lacks background, and allows a clean and sharp viewing of the histological preparation.