Background: Quality of nursing service as an indicator of health service quality becomes one of the determinant factors of health service institution reputation in the public. To improve the quality of nursing care is through supervision activities conducted by the room coordinator. Supervision that has been running in RSUD Panembahan Senopati Bantul was only with the format and mechanism limited to the activity of the room. Aim: To know the effectiveness of the use of clinical supervision instrument developed toward the improvement of nurse performance indicator achievement in Panembahan Senopati Hospital Bantul. Method: This is a quasi-experimental research with Pre Post-test design with control group design. The subjects of this study were all nurses at the inpatient ward of Panembahan Senopati Hospital Bantul amounted to 137 nurses. Data analysis was done by independent T-test. Results: The Implementation of nursing supervision showed that as many as 55.7% nurses perform nursing assessment, 52.5% nursing action plan, 75.4% nursing care, and 32,8% nursing evaluation. Nurse performance indicator achievement before and after the use of the instrument of clinical supervision at nurseshowed an increase of average from control group to treatment in every aspect of the performance indicator. Statistically, the use of clinical supervision instrument developed for nurses in Panembahan Senopati Bantul Hospital is effective to improve the nurse performance. Conclusion: The developed clinical supervision instrument can improve nurse performance indicator achievement at Panembahan Senopati Hospital Bantul. Keywords: Clinical Supervision, Performance Indicator, Supervision