The aim of this study is to examine the relationships between attachment style and prosocial behavior of the university students. The research which is used relational survey method was carried out on 551 students who are among 1st and 4th grades and are attending to Kırıkkale University in the 2018-2019 academic year. Prosocial Scale which is developed by Carlo and Randal (2002) and is adopted by Yıldız, Boz and Yıldırım (2012) to university students and Interpersonal Attachment Styles Scale which is developed by Kandemir and İlhan (2017) are used in the research as data collection tools. Path analyse method was used by utilizing AMOS package programs in order to analyse hypothesis test model. As a result of the research, it is revealed that secure attachment style of the university students has a precursor power which is significant and positively on Compliant Prosocial Behavior and is significant and positively on the anonymous/altruist behavior. According to reserach findings, anxious attachment sytle has positive and significant effect on predicting public prosocial behavior and pragmatic prosocial behavior. There withal the avoidant attachment style predicts public prosocial behavior positively and substantially and pragmatic prosocial behavior positively and substantially. The findings obtained after the analysis of research are discussed by comparing with the literature study results. In the last part of the research, suggestions are made within the results of the study.