Purpose: Drawing on semi-structured and focused-group interviews performed with various pre-service mathematics teachers and in-service mathematics teachers, the present study benefits from the frame of teacher identity to make the meaning of heterogeneity among their experiences and perceptions of mathematics teaching anxiety. The current study aims to reflect how the participants perceive and describe their experiences and perceptions about mathematics teaching anxiety through their teacher identity in this phenomenological research. Method: This research was designed based on phenomenological research. The data collected through interviews and focused-group interviews were analyzed through two stages. Initially, the participants' teacher identity was identified by the manual developed by Beijaard, Verloop and Vermunt's (2000) identity framework through the deductive approach. Afterwards, the transcripts of the interviews were examined by content analysis. The data collected through interviews were analyzed through two stages. Findings: The horizons and themes identified through the content analysis were represented through their characteristics of professional identity under three titles: the horizons experienced and perceived by IMTs and PMTs; the horizons experienced and perceived by only PMTs; the horizons experienced and perceived by only IMTs. Moreover, how the participants' experiences and perceptions about the phenomenon of mathematics teaching anxiety differentiated based on teacher identity characteristics were reported. Implications for Research and Practice: Interventions that may reduce the MTA of PMTs and IMTs can be designed more systematically and beneficially by considering the themes that emerged in the study and differences based on teacher identity.