Relationships are among the most important and powerful aspects of sports marketing. In other that, one of the most important approaches in relationship marketing is relational benefits that indicate success or fault in relationship marketing implementation. Thus the present article has studied effect of relational benefits includes confidence, social, special treatment and respect benefits on customer loyalty. Also this paper presents a framework for understanding how and why consumers engage in relationship marketing. This study is a descriptive study was conducted through a survey and its population of research was made up of whole customers of bodybuilding centers in Rasht city (N=210). The data gathering instrument was questionnaire and its validity was investigated via exploratory and confirmatory factor analysis. The result of exploratory factor analyze indicate relational benefit include confidence, social and special treatment benefit. Indeed in this present study underpinning of relational benefit are three, confidences, social and special treatment benefit. Furthermore, result indicates that relational benefit (confidence, social and special treatment benefit) had significant and positive effect on customer loyalty.