The aim of this study is to describe and interpret how pedagogy students build their professional identity during professional practices, from their subjective theories. An interpretive descriptive study and qualitative methodology were used. The sampling is of a theoretical type and is made up of 7 students from three pedagogy careers at a public university in the Atacama region, Chile. Episodic interviews and a discussion group were applied. The Grounded Theory was used, obtaining as results subjective theories about the sense and meaning of the professional teaching identity and the teaching profession, the process of construction of the professional identity, the characteristics of the constructed identity and suggestions for this training process. In addition, an explanatory model of the construction of professional identity in the context of professional practice was developed. In the discussion and conclusion, the findings are analyzed in light of the literature. © 2025 Elsevier B.V., All rights reserved.