Abstract: Purpose - This research aims to examine the role of knowledge management infrastructure in enhancing service innovation in private professional training centers in Saudi Arabia. Design/methodology/approach - The knowledge management infrastructure factors considered in this study are organizational culture, organizational structure, information technology, a community of practice, and physical environment. A quantitative research method was used, and the data was collected from 200 employees at these centers through a questionnaire that contained 30 items. Correlation and regression analyses were conducted to test the research hypotheses. Findings - The results of this research indicate that knowledge management infrastructure has a statistically significant, positive impact on service innovation in private professional training centers in Saudi Arabia. The knowledge management infrastructure factors that have the highest level of positive impact on service innovation are information technology and organizational culture, followed by the community of practice, the physical environment, and organizational structure are statistically significant positive impacts on service innovation. Limitation of research - This study concentrated only on the private professional training sector. Furthermore, the sample size is small, and the convenience sample technique that was utilized may not represent the entire population. Originality/value - This research offers a unique empirical direction for service innovation in private professional training centers in Saudi Arabia. As there is a lack of empirical studies regarding service innovation in these training centers in Saudi Arabia. The empirical evidence obtained from this study can contribute positively in enhance service innovation through knowledge management infrastructure. Recommendations - Based on the result of this research, the provided recommendations can be beneficial for organizations to achieve service innovation through investing in knowledge management infrastructure. Keywords: Knowledge Management Infrastructure, Service Innovation, Private Professional Training Centers, Saudi Arabia.