This study examines that the participation in an introductory special education course can influence pre-service teachers’ intention to implement instructional adaptations for students with disabilities at elementary school. The subjects of this study are 489 preliminary teachers who enrolled in the Busan national university of education. The questionnaires are composed of background information, teaching efficacy, and instructional adaptations. The subjects are divided into two groups: One includes 277 pre-service teachers who took a mandatory course, 'introduction to special education' and the other includes 212 pre-service teachers who had no chance to take the course. The collected data are analysed by descriptive statistics and t-test to find out the differences between two groups about the teacher-efficacy and the intention to implement instructional adaptation. The results of this study are as follows: There aren't statistical differences between two groups about the preliminary teacher's the teacher-efficacy through special education course. Significant differences in total instructional adaptations and three sub-instructional adaptations(e.g., instructional environment, instructional contents, and instructional evaluations) were found between preliminary teachers through special education courses.