This study begins with the problem of the fact that three concepts are used interchangeably: colleagueship, collaboration, and collegiality. The purpose of this study is to compare and analyze these three concepts through literature analysis and demonstration, and to explore the concept of teacher collegiality based on the results. The results are as follows. First of all, we explored the conceptual structure of colleagueship. It was found to be composed of professionalism, collegiality, and collaboration as the core elements of the conceptual structure of colleagueship. In addition, since the concept of colleagueship presupposes the process factor of collaboration, the conceptual aspect of colleagueship [ Type  ~ Type  ] was additionally presented in consideration of the quality and motivation of collaboration. Next, we explored the concept structure of teacher colleagueship based on the results of exploring the concept structure of colleagueship. Based on logical reasoning, it was found to be composed of teacher professionalism, teacher collegiality as a conceptual factor, and teacher collaboration as a process factor on the concept of teacher colleagueship structure. Lastly, we presented the implications for teacher colleagueship in educational administration in terms of conceptual and practical aspects. Based on the results of this study, the suggestions are as follows. First, there is a need for clear recognition of the concept of teacher colleagueship. Second, a more detailed exploration of the concept and composition of teacher colleagueship is needed.