This study was carried out to analyse comparatively, the foundations of organizational behaviour among the staff of Shiraz University. In this regard, based on the subject's theoretical and research background, the foundations of organizational behaviour were formed of three dimensions (individual, group and organizational) and 23 related factors, and according of which research tool (questionnaire) was formulated and reliability and validity of it were confirmed. The questionnaires were completed by 250 participants who were selected among 1100 university staff, using stratified random sampling method. The results of one sample T- test showed that the mean of individual dimension effect on staff behaviour was high (X− > Q3) and the means of group and organizational dimensions effects on staff behaviour were medium (Q3> X− > Q2). Also, the results of ANOVA suggested that among the individual factors, ability had the highest effect and biographic characteristics had the lowest effect on staff behaviour. Among group factors, leadership had the highest effect and organizational politics had the least effect on their behaviour. And among organizational factors, job analysis had the highest effect and the environment had the lowest effect on their behaviour. Furthermore, organizational behaviour dimensions in order of their influence on the behaviour of the staff include; individual, organizational and group dimensions. Also, factors influencing staff behaviour include ability, personality, intelligence, leadership, learning, job analysis, organizational culture, organizational climate, group characteristics, motivation, attitude, belief system, technology, strategy, perception, power, structure, biographic features, communication, environment, social capital, organizational conflict and politics.