This study aimed to examine the effect of digital leadership on sustainable knowledge management, with emphasis on the mediating role of knowledge sharing in knowledge-based companies. The study was applied in terms of purpose and employed a descriptive-survey, cross-sectional research design. Data were collected from employees of knowledge-based companies using a structured questionnaire and analyzed through Structural Equation Modeling (SEM) using SmartPLS. Findings: The results showed that digital leadership had a positive and significant effect on sustainable knowledge management (β=0.587, T=3.408, P=0.001). Digital leadership also had a positive and significant effect on knowledge sharing (β=0.604, T=3.929, P<0.001), while knowledge sharing positively and significantly affected sustainable knowledge management (β=0.518, T=4.738, P<0.001). Furthermore, the indirect effect of digital leadership on sustainable knowledge management through knowledge sharing was positive and significant (β=0.313, T=3.343, P<0.001), confirming the mediating role of knowledge sharing in this relationship. Conclusion: The findings indicate that digital leadership contributes to sustainable knowledge management not only through direct managerial actions and decisions but also by creating favorable conditions for interaction, knowledge exchange, and knowledge flow among employees. Accordingly, in knowledge-based companies, the effectiveness of digital leadership in promoting the preservation and sustainable development of organizational knowledge depends partly on establishing appropriate conditions that facilitate knowledge sharing.