Background. Student reasoning in learning mathematics contributes significantly to the achievement of student mathematics learning outcomes. The main objective of this study is to investigate the process of reversible reasoning in students for inverse problems, in the case of Adjie (Ad). The research method used to reveal the reversible reasoning in Adjie's case using descriptive qualitative research methods. Sampling was carried out using purposive sampling technique where the research sample was selected based on reversible reasoning criteria. Retrieval research data uses the results of students' mathematical work, think aloud, interviews, and the components that cause reversible reasoning. The results of our study found that the process begins with an obstacle that causes Ad to be unable to continue the resolution process, resulting in a metacognition process by analyzing the problem again analytically and developing other heuristic strategies. Ad shows a change in perspective where he initially interpreted inverse as the act of swapping independent and dependent variables and switched to interpreting inverse as the opposite of a function process involving analogy and image representation. The contribution of this research provides knowledge that reversible reasoning can occur in understanding and solving mathematical problems in inverse material.