In this study, the aim is to determine pre-service teachers' conceptual understanding of the standing wave concept. Pre-service teachers' conceptual understanding of the standing wave concept was determined through the phenomenological pattern, and the aim was to lay bare how they made sense of this phenomenon, how they perceived and experienced it. The study was conducted with the participation of 13 pre-service teachers. One closed-end question was used to determine pre-service teachers' demographic characteristic, and five open-ended questions were used to determine their conceptual understanding of the standing wave concept. Data were obtained through semi-structured interviews conducted individually with the pre-service teachers. Because their answers varied, they were defined and analyzed through a new map with "Answer Sculptures." At the end of the study, it was determined that pre-service teachers have issues with their conceptual understanding of the standing wave concept; they have incomplete and non-scientific information. It was also seen that only a couple of pre-service teachers have a complete understanding of the standing wave concept.