Reflective practice has become an integral component in teacher education. Many studies have investigated the development of a teacher’s reflective practice, but less attention has been paid to novice L2 teacher trainees’ development of reflective practice. Similarly, little is known about their concerns, interest, and needs, as they manifest in reflection. This study, therefore, identifies reflective themes that teacher trainees concern about after microteaching. It further examines whether teacher trainees’ reflective focus differs depending on their knowledge and experience in the teacher education program. Seventeen teacher trainees, who were either in the beginning or advanced L2 teaching courses, reflected about their microteaching, and their written reflections were analyzed by their contents. Seven themes emerged, which include teacher behaviors, classroom management, planning, microteaching context, language-specific features, student learning, and teacher roles. Overall, teacher trainees focused more on teacher behaviors and their self-image in relation to classroom management and lesson planning than issues on student learning and teaching. It was also found that this tendency was stronger for beginning trainees than advanced trainees. These findings are discussed in light of the development of reflective practice.