In this study, it is aimed to evaulate the sport customers' perceptions of the service quality and the sport businesses'performance in Sivas, Turkey and with the gained data to improve some advices for sport businesses to give more effective service quality. The data which is used in this study have been gained from the customers of 10 sport businesses in Sivas, Turkey. SQAS (Service Quality Assessment Scale) instrument, which was developed by Lam et al., (2005), to measure the service quality of Fitness Centers, was used as a means to collect data. The data used in the research were obtained from the customers (n=316) of 10 sport businesses in Sivas province. To find the difference between groups, "irrelevant-modelling t test" and "paired-modelling t test" have been used. The difference between them has been accepted as meaningful if p<0.05. When the service expectations according to the gender are compared, it is seen that the females have higher expectation levels in all aspects than the males. When the service perceptions according to the gender are compared, it is seen that the females in all aspects except "physical establishment" have found the service quality more satisfying than the males. The results indicate that the expectations of the customers of sport businesses in Sivas, (Turkey) province are not met completely. All the customers that get service from the sports institutions in the city of Sivas have the satisfaction more than the avarege, but their expectations haven't been fully met. It has been determined that there is a meaningful difference between the expectation and perception scores in the negative direction. It is seen that the aspect that has the lowest expectation level is "undressing room". "Training center", "personnel", "program" and "physical establishment" aspects follow "undressing room" aspect in order. [ABSTRACT FROM AUTHOR]