Derivative concept is one of the essential studies in calculus, which is studied in teaching mathematics. Prospective mathematics teachers who have completed their studies and later become teachers will teach derivative concepts to their students at school. Therefore, knowledge of derivative concepts is vital in transforming knowledge to students. This study aimed to investigate concept images of prospective mathematics teachers on derivative representations. The research design in this study used a qualitative with case study approach. The participants were prospective mathematics teachers at a university in West Java, Indonesia (N=29). The research data was obtained from the test and clinical interview. The findings of this study show that the concept image of all participants on the derivative concept is still limited in function representation. Concerning the meaning of the derivative concept, most participants only view the derivative concept as a tool to solve procedural problems. It concluded that the representation of participants still did not support conceptual understanding of the derivative concept. It is the impact of the teaching design that given. Based on these findings, educators are expected to be able to improve the quality of teaching derivative concepts in the future by using various contexts or representations so that the concept image formed is more comprehensive to support conceptual understanding in learning of derivative concepts.