ABSTRACT Teacher development involves the dynamic interplay between emotional intelligence and emotions. While previous research links these factors with their professional identity, teaching enthusiasm, and teacher-student relationships, the development characteristics of emotional intelligence and emotions remain unexplored in relation to these outcomes. In a two-year study with 357 novice teachers, emotional intelligence and emotions were tracked thrice. Data on professional identity, enthusiasm, and teacher-student relationships were collected at the final assessment. Latent growth curve modelling results revealed that only positive emotions, not negative ones, mediate the connection. Specifically, the initial level of positive emotions mediated the link between the initial level of emotional intelligence and teaching enthusiasm, professional identity, and teacher-student relationships. The growth rate of positive emotions notably mediated the relationship between emotional intelligence and professional identity, teaching enthusiasm, and teacher-student relationships. These findings offer new insights into the development of teachers’ emotional intelligence, emotions, and professional growth.