Recent studies on employee motivation and organizational citizenship behaviour (OCB) has focused on the effect of motivation on OCB in general. This study explores the association between intrinsic motivation and dimensions of OCB relationship based on the administrative staff of Sri Lankan state universities. The focus of this study was to analyze the effect of extrinsic motivation on dimensions of organizational citizenship behaviour of administrative staff of 15 state universities in Sri Lanka. Established questionnaires were used to collect data. A total of 168 questionnaires were used for the analysis. The data was analyzed by SPSS package.. It can be concluded that, out of five dimensions of OCB, four dimensions having direct and positive impact from intrinsic motivation. The study found that intrinsic motivation has positive impact on altruism, conscientiousness, sportsmanship and courtesy. But the present study does not confirm the relationship between intrinsic motivation and civic virtue.