This study aims to analyze the implementation of polycentric governance in public tax services at KPP Pratama Jambi Telanaipura and to assess its effectiveness in improving service quality. This research uses a qualitative approach with a case study method, where data were collected through semi-structured interviews, documentation, and observation involving key informants such as office leaders, section heads, staff, and taxpayers. The results indicate that the application of polycentric governance is reflected through the presence of multiple actors, self-organization, overlapping authority, and strong coordination and collaboration among work units. Each unit operates with relative autonomy while remaining interconnected in achieving common goals. In terms of public service quality, the indicators of tangibles, reliability, responsiveness, assurance, and empathy have been adequately fulfilled. Furthermore, the implementation of this governance approach has contributed to improving service effectiveness, as evidenced by stable and high service performance, enhanced responsiveness, and strengthened public participation through activities such as public hearings and tax education programs. However, challenges such as limited resources and overlapping authority remain. Overall, polycentric governance has a positive impact on enhancing the quality, effectiveness, and accountability of public tax services.