Epstein Barr virus (EBV) has become increasingly recognized as one of the causes of cancer in humans and in Nigeria, its seroepidemiology, has not been fully elucidated. EBV vaccination is not a part of the Expanded Programme of Immunization (EPI) therefore, immunization against the virus is non-existent. This study was conducted to assess the seroprevalence of EBNA IgG antibody in patients in Port Harcourt, Nigeria. Demographic data and sera were collected from 80 consenting patients of different gender and ages from the University of Port Harcourt Teaching Hospital, Rivers State. Their sera were screened for EBV IgG antibodies using enzyme linked immunosorbent assay (ELISA) kit (DIA.PRO Diagnostic Bioprobes, Milano). Of the 80 sera evaluated for EBV Immunoglobulin G antibody, 68 (85%) were positive and 12 (15%) were negative. Seropositivity rate was higher in males (89.3%) than in females (82.9%). Patients within 21-25years had the highest prevalence rate of 87.2%. Age and gender were not significantly associated with the seroprevalence of EBNA IgG antibodies. From the result, the immunity gap in the population is significant. Hence, there is need for vaccination of susceptible individuals in order to ensure the control and elimination of Epstein Barr virus in Nigeria.