Collective behavior is regarded as one of the main issues in contemporary political sociology, a social phenomenon that has long challenged political systems. The purpose of this paper is to study the factors affecting the tendency of the students of Shiraz toward collective behavior. To explain collective behavior, we have used Neil Smelser’s theoretical framework and from the structural-functional perspective, collective behavior and the factors affecting it have been identified. The sample consisted of 410 students, selected from a statistical universe of 9326 students. We have used random startified sampling method and Kochrans's technique of calculating the volume of the sample. The results show that the variables age, parents’ education, using television, the internet, satellite, gender, marital status, employment status, place of residence, social background and ethnicity have a significant relationship with the students’ tendency toward collective behavior. The multi-variable regression analysis shows that the amount of using Internet and watching television as well as gender are the most significant variables, explaining 15.1 percent of the changes of the dependent variable. Generally, the findings show that the amount of using Internet has the greatest positive relationship with collective behavior. This is followed by the variables the amount of watching television and age, which are negatively related with collective behavior.