Abstract This study investigates how practicum EFL teachers build trust through appraisals in classroom interactions at a local senior high school in Mainland China. Building upon prior research on trust discourse and appraisals, we present a model of teachers’ trust discourse, which we apply to analyze six English reading lessons conducted by three young EFL practicum teachers. The findings reveal that the practicum EFL teachers construct two distinct types of trust: cognition-based trust (CBT) and affect-based trust (ABT). CBT is formed through the communication of the teachers’ epistemic and deontic authority, while ABT is fostered by emphasizing values congruence and guanxi (interpersonal connections) between the teachers and the students. Appraisals play a crucial role in the trust-building efforts of the practicum teachers. Our analysis further indicates a preference among the practicum teachers for prioritizing CBT, as evidenced by their strategic use of appreciation and judgment resources in the attitude system, as well as the application of force resources in the graduation system. This study provides valuable insights into the pivotal role of appraisals in cultivating trust between EFL teachers and students in classroom settings.