The purpose of this study is to analyze the characteristics of teacher research in Korea through a systematic literature review and to suggest future tasks. For this purpose, 51 teacher-research articles published in accredited (and candidate) journals were selected, and trends in research periods, participants, and methods were analyzed. In addition, the developmental tendencies of teacher research proposed by Cochran-Smith and Lytle (1999) were employed as an analytical framework to examine its domains and conceptual and theoretical frameworks. The major findings are as follows. First, teacher research in Korea has gradually expanded since the mid-2000s. In terms of research participants, studies conducted solely by teachers and collaborative studies between teachers and professors emerged as the primary forms. Regarding research methods, qualitative approaches predominated, with action research and narrative inquiry most frequently utilized. Second, in terms of research domains, studies linking curriculum and teacher professionalism were relatively numerous, whereas research connected to teacher education, school improvement, and social reform was limited. Third, the analysis of conceptual and theoretical frameworks revealed that studies emphasizing social inquiry and knowing in communities were relatively common, while those corresponding to practical inquiry were fewer in number. Based on these findings, this study argues for clarifying and expanding the concept and boundaries of teacher research while maintaining its essential nature as systematic inquiry into educational practice, and for extending it beyond curriculum and instruction. It also highlights the need for historical analyses of its development and for secondary research on teacher research.