This qualitative study conducted to understand the experience of healthy volunteers participated in clinical trials. The participants were adult health volunteers who participated in the first phase clinical trial. Data were collected in individual in-depth interviews, and analyzed by thematic analysis method. As a result of the study, 15 meaningful codes and 6 sub-themes were derived. The 3 core-themes that were derived: overcoming perception of clinical trials, completing clinical trials, and participating in clinical trials as contributors. Participants were trying to complete the clinical trial while experiencing ambivalence of self and negative perceptions of the society as well as feeling uncomfortable and anxious about clinical trial. And they felt sorry for the difficult documents and the formal process and wanted to be treated more as a clinical trial contributor. Therefore, it is suggested that there is a need to improve social awareness of clinical trials and to consider and take a holistic approach to health volunteers.