Purpose This paper attempts to review and conceptualize how different scholars approach the research on teacher identity through the lens of three human interests defined by Jürgen Habermas. Design/Approach/Methods This literature review, guided by Habermas's three human interests, illustrates the characteristics of three different approaches to the inquiry into teacher identity. Findings This paper summarizes three approaches to researching teacher identity and their characteristics, namely the technical approach, the practical approach, and the critical approach. The implications for future research and teacher development are also discussed. Originality/Value Through incorporating Habermas's three human interests into teacher identity inquiries, this article offers a theoretical narrative review of the approaches to investigating teacher identity. Strengths and weaknesses of each approach as well as the possibility of a combined application of different approaches provide an original discussion on teacher identity research.