The aim of this study was to identify the factors influencing the loyalty of football players to sports apparel brands in the eleventh round of the Iranian Premier League. The methodology of this research was surveying, and the studied population was formed of players who participated in the eleventh round of Premier Football League (n=426). The final study sample included 263 members of the Premier League. The questionnaire for data collection on brand loyalty was based on that used by Wong Foong and yahyah (2008) with the reliability of (a=0.73). Analysis was done using ANOVA (analysis of variance) with repeated measures, and Bunfrony comparison test at a significance level of 0.05 was conducted with spss19 software. The results showed that the factors of product quality, its brand, and its model were more effective than other factors on the loyalty to a sports apparel brand. Therefore, managers and planners of the sportswear industry should try to create or modify their models to increase the brand loyalty and the product quality with which to provide a basis for increasing the rate of customers’ loyalty and, thus, to provide for long-term interests of their business.