Background: Today, intense competition in health environment needs induction and diversion of values added to health service customer such as, internal marketing activities and organizational citizenship behavior enable nurses to provide health services with high quality and increasing hospital productivity and profitability Aim of the study: Find out the relation between the nurses perception of their organization internal marketing activities and organizational citizenship behavior Design: Descriptive, comparative design. Setting: At gastroentroentrology surgical center and Mansoura general hospital. Subjects and methods: The study sample composed of 293 nurse . Data was collected by using (Multifactor of internal marketing questionnaire and Organizational citizenship behavior questionnaire) Results: revealed that there was statistically significant relationship between internal marketing and organizational citizenship behavior (P<0.05). conclusion: most of nurses have low perception toward internal marketing activities ,and majority of them have (high- moderate ) level of agreement concerning organizational citizenship behavior. Recommendation: Mangers should develop a plane for internal marketing application in their hospitals to enhance their health service quality also, selecting, retain, evaluating nurses for organizational citizenship behavior. In addition, Provide good work environment to nurses ( providing possible supplies that make their work easy and interesting) and collaborative atmosphere ( encourage colleagues to help other especially with heavy work).