Background. Horse riding is one of the oldest sports competition in Iran held annually in provinces such as Golestan. However, the number of spectators present in these competitions is not comparable to sports such as football. Objectives. It's necessary to study the behavioral tendencies of the Spectators of horse racing and its influencing factors. Methods. It was a descriptive survey study and the statistical population included all spectators of horse racing of the Eighth Week Spring competition in Gonbad Kavoos, 2018 which included 3480 individuals. According to Cochran formula, 348 people were selected by available sampling method. Cheng et al. ( 2012) questionnaire was used for data collection of planned behavior model and Lee and Shiu (2015) questionnaire for tendency of spectator's involvement at sporting event and spectators' re-attendance questionnaire of Rio and et al (2011) were used. The internal consistencies of the questionnaires were obtained by Cronbach's which were 0.89, 0.85 and 0.78, respectively. Structural equation modeling was used to test the research model. Results. The findings showed that the effect of attitude (β = 0.23, t = 3.74), subjective norms (β = 0.15, t = 2.78) and perceived behavior control (β = 0.35, t = -5.93) were positive and significant on the tendency of involvement of spectator in Horse Racing. Moreover, the effect of attitude (β = 0.34, t = 6.55) and perceived behavior control (β = 0.04, t = 0.83) were positive and significant on the spectators' re-attendance to Horse Racing. Finally, the findings showed that the effect of subjective norms was not significant on the spectators' re-attendance (β = 0.16, t = 2.37). Conclusion. It can be concluded that the planned behavior model can be used to explain the behavioral tendencies of horse racing spectators during the Gonbad kavoos spring competition. Finally, increasing spectators' knowledge of horse racing, offering attractive and entertaining programs for spectators during competitions and developing various promotional strategies to increase involvement and a desire for Horse Racing Spectators re-attendance are suggested for these competitions.