It is the aim of this empirical study to explore the relationship between two types of Religiosity (Intrinsic and Extrinsic) and Organizational Citizenship Behavior of Public health sector doctors, by observing how the level of their organizational commitment mediates this relationship. The mediating role of Organizational Commitment is determined by taking its three components; Normative Commitment, Affective Commitment and Continuance Commitment from the Meyer and Allen model. This relationship is determined by observing the direct impact of Religiosity and Organizational Commitment on Organizational Citizenship Behavior and also the indirect impact of the three types of organizational commitment on the association between religiosity and organizational citizenship behavior. The data for this study was collected by pencil and paper questionnaires from 214 doctors of public hospitals using a probability sampling technique. The analysis of the results, validated through SPSS software proved that all the relationships hypothesized had a positive correlation with each other and were accepted. A conceptual model was proposed to show the relationships between these different variables. Supervisor : Dr Khurram Shahzad