Background Teachers' verbal immediacy behaviors play a important role in enhancing student engagement, motivation, and emotional security. However, as the role of smart classrooms in education becomes increasingly prominent, research on the formation mechanisms of teachers' verbal immediacy behaviors in smart classroom environments remains relatively limited. Especially, at the primary grades, research on teachers' verbal immediacy behaviors has not yet garnered sufficient attention. Methods This study integrates the theory of planned behavior (TPB) with the norm activation model (NAM) to propose a theoretical model for teachers' verbal immediacy behaviors in smart classroom environments. Using purposive sampling based on specific criteria, 855 Chinese primary school teachers with extensive experience in smart classroom instruction were selected as participants. Data were collected through a structured questionnaire survey and analyzed employing structural equation modeling (SEM) to test the hypotheses empirically. Results This study finds that teachers' verbal immediacy behavioral attitude, perceived behavior control (PBC), personal norms (PC) and subjective norms (SN) have significant positive effects on teachers' verbal immediacy behavioral intention. Awareness of consequences (AC) had significant positive effects on ascription of responsibility (AR), teachers' verbal immediacy behavioral attitude. In addition, Smart classroom environments have a moderating effect on the relationship between the teachers' verbal immediacy intention and their verbal immediacy behaviors. Conclusion This study integrates the TPB and the NAM to explore the formation mechanisms of teachers' verbal immediacy behaviors in smart classroom environments, revealing the positive influence of smart classroom environments on these behaviors. Implications The findings provide a theoretical foundation for understanding primary school teachers' verbal behaviors in smart classrooms and offer valuable insights for optimizing the design of smart classrooms and enhancing teaching effectiveness in educational practice.