We know that teachers' identities and their ideological assumptions of teaching and learning mathematics are critical in influencing their teaching and thinking about classroom practices. To better understand prospective mathematics teachers' identity during teacher education, this study investigates how two participants negotiate their identity within the different ideologies they experience during their teacher education program. This study takes the position that prospective mathematics teachers' identities are understood in terms of the narratives they construct and tell about themselves and others. By using Interpretive Phenomenological Analysis (IPA), this study reveals that the participants either experienced a non-negotiation of identity or a negotiation of a new identity. We know that prospective mathematics schoolteacher's identity and ideology have substantial consequences for the teaching and learning of mathematics. The educational ideology of mathematics, within the context of their teacher education program, can further shape the prospective teacher's identity about the discipline. This study suggests greater focus on prospective mathematics teacher identities and ideologies and indicates the support they need through teacher education to be equipped for their future role as mathematics teachers.