Objectives: The present study aimed to clarify supervisor feedback on the reflective journals of nurse managers in the early years of supervisory role. Methods: A total of 63 nurse managers participated in an experiential learning-based program that included writing entries in a reflective journal and supervisor feedback. The Experiential Learning Inventory on the Job (ELI) was administered before and after the program. Overall, 10 nurse managers showed apparent changes in their Experiential Learning Inventory scores after completing the program. We qualitatively analyzed the data from 41 reflective journal entries written by these 10 nurses along with the written feedback from their supervisors and subjected the data to descriptive analysis. Results: The analysis yielded the following seven themes: "suggestions on how to describe the situation", "questions to clarify important information", "positive feedback on the nurse manager's thoughts and actions", "analyzing circumstances from the supervisor's viewpoint", "clarifying learning points for the nurse manager", "demonstrating actions the nurse manager should take" and "suggestions on how to develop learning points from experience". Discussion: In this study, we provided specific contents of supervisor feedback provided to 10 nurse managers who showed apparent changes in their ELI scores after completing an experiential learning-based program to foster competence among nurse managers. We believe the feedback provided by the supervisors in this study might promote experiential learning among nurse managers. Limitations: Because there were only 10 study participants and all had apparent changes in their ELI scores after completing the experiential learning-based program, caution should be exercised in generalizing the results of this study to other groups. To confirm the present results, in the future, it is necessary to investigate supervisor feedback in different subjects, such as nurse managers who did not show changes in their ELI scores after completing the program. Conclusion: Qualitative and descriptive analysis revealed seven themes for supervisor feedback on nurse managers' reflective journals.