Purpose: This study sought to investigate the critical features of Word of mouth (WOM) advertising and their impact on sport consumer behavior. Research design, data, and methodology: Target population of the study consisted of all sports consumer of the Federation of Special Patients and Organ Transplantation, Tehran (Iran), who had indirectly watched the World Organ Transplant Competition documentary at least once on others' advice. For this purpose, 360 sports consumers of the federation were purposefully selected and they were asked to complete the standard WOM advertising questionnaire of Asda and Ko. Pearson correlation coefficient test and modeling of structural equations were performed using Spss24 and Smart PLS software at an error level of 0.05 used to analyze the data. Results: The findings show that there is a significant relationship between experience and expertise, trust and validity, content richness, and the power of message transmission through WOM advertising and its predictability. Finally, interpersonal relationships and work involvement also had a moderating role in this regard. Conclusions: The general conclusion is that the components of WOM advertising as well as involvement and homophily with the mediating role directly as one of the presuppositions for persuasion. The sports consumer was promoting WOM.