The current study adopted a longitudinal design to investigate 105 EFL teachers' belief change after a three-month teaching practicum. Pre-test and post-test questionnaires were administered before and after the practicum. Repeated measures and t-test data analyses were used to examine differences across different aspects of beliefs, and differences of teachers' beliefs before and after the practicum. Further content analyses of interview and reflective journals were conducted to find out the change and its potential factors.