The management of a fitness center needs to apply good management functions in order to improve the quality of its service. HSC Fitness Center is one of the public services which are engaged in physical fitness. The purpose of this study was to determine the impact of the application of management functions on service quality at the HSC Fitness Center Yogyakarta. This research uses qualitative and quantitative approaches (mixed method) with data collection techniques through observation, interview, documentation and questionnaire methods. The data sources of this study consisted of directors, managers, front office staff, fitness instructors and members of the HSC Fitness Center. Data collection on the application of management functions is obtained from observations and interviews with data sources, while data on service quality is known by using an instrument in the form of a questionnaire. Based on the results of research and discussion, it can be concluded that the overall HSC Fitness Center Yogyakarta has implemented management functions in the form of planning, organizing, placing, directing, and controlling optimally. This implementation has a positive impact on service quality which includes several factors: reliability, tangibles, responsiveness, assurance, and empathy.