Hostile and instrumental aggression are very popular among soccer fans, The goal of hostile aggression is just to cause harm to the target like rival fans while instrumental aggression refers to actions intended to harm another person with the goal of achieving a result, such as assisting their favourite team to win the match. The body of research on sport fans’ violence shows that this aggression emerges through various social, psychological and situational factors. Thus, a few factors such as team identification, sport identity and team’s performance are crucial but hardly considered in Iranian research. However, the purpose of this current research is to examine the impact of aforementioned factors on instrumental and hostile aggression in football stadiums. The paper uses the social identity theory and survey method for data collection. The results of Mann-Whitney U test among 356 male spectators from the Padideh football club, demonstrate that fans that have high sport and team identification, also have more willingness to commit hostile and instrumental aggression compared with those with low sport and team identification.
