While pre-service teachers’ beliefs about different dimensions of English language teaching have been widely researched, little is known about their beliefs related to English for Specific Purposes (ESP). This article reports on three Vietnamese pre-service teachers’ beliefs about ESP teaching, captured over a six-month period. Data from semi-structured interviews, stimulated recall interviews, observations, and reflective journals were collected at two critical points in the teacher education programme: the methodology course and the practicum. The findings add fresh insights into pre-service teachers’ beliefs, particularly how these beliefs may change over time. The three case studies presented in this paper illustrate how participants developed their beliefs. The six belief changes identified are then discussed in terms of levels (from no to significant change) and the underlying motives. Implications are also discussed for teacher educators in designing or improving teacher education programmes and for researchers interested in pre-service teachers’ belief change.

虽然职前教师对英语语言教学不同维度的信念已被广泛研究，但人们对他们与特定用途英语 (ESP) 相关的信念知之甚少。本文报道了三名越南职前教师在六个月内对 ESP 教学的看法。来自半结构化访谈、刺激回忆访谈、观察和反思日记的数据是在教师教育计划的两个关键点收集的：方法论课程和实习。研究结果为职前教师的信念提供了新的见解，特别是这些信念如何随着时间的推移而改变。本文提出的三个案例研究说明了参与者如何发展他们的信念。然后根据级别（从无变化到重大变化）和潜在动机对确定的六种信念变化进行讨论。还讨论了对教师教育工作者设计或改进教师教育计划以及对职前教师信念改变感兴趣的研究人员的影响。