The Nigerian health sector has over time remained in a bad state. This study investigated the factors influencing knowledge utilization by policy makers in the Nigerian health sector adopting the Chatman's theory of normative behavior as a theoretical framework. To achieve the objectives of this study, the study formulated three research questions. A qualitative research methodology was adopted. Interview using a recorder was the instrument used in data collection. The study focused on narratives gotten from Federal Ministry of Health officials who are directly involved in the management of hepatitis B in Nigeria. Seventy six narratives explaining factors influencing knowledge utilization by policy makers in the Nigerian health sector were identified and were further collapsed into sub-categories and categories. Findings from the study revealed the influence of socio-cultural factors such as Negligence, Selfishness, Lack of political will, lobbying and Corruption, on the use of knowledge by policy makers in the Nigerian health sector particularly in the management of hepatitis B in Nigeria. Using Chatman's theory of normative behaviour the findings suggest that an environment that will encourage the use of knowledge should be created at all levels of Government.