Background and purpose:Taking the medical terminology course is usually problematic for students with worse language learning confidence. Content and lan-guage-integrated learning (CLIL) is a student-centered and practical teaching ap-proach. Few studies have examined the effect of CLIL on students’ confidence while learning medical terminology. This study explored the influence of CLIL on the stu-dent’s confidence in the medical terminology course. Methods:This study was quasi-experimental with a convenience sample that used a single-group, pre-post research design. This research was conducted at a university in northern Taiwan. The demographics, learning confidence, academic performance, and student satisfaction were evaluated using the structured questionnaire. Levels of learning confidence were analyzed by using the generalized estimating equation. Results:A total of 36 undergraduate students were recruited. Academic performance on the midterm was positively correlated with learning confidence on the final test (p = .033). With learning confidence divided into four subscales, the scores of skills enhancements, goal achievement, and speaking confidence showed an increase between the pretest and midterm (p < .001, < .001, and < .001, respectively) and between the pretest and final test (p = .033, .005, and < .001, respectively). Conclusions:This result identi-fied the benefit of teaching medical terminology via CLIL based on improving stu-dents’ learning confidence. CLIL is a practical design for enhancing students’ confi-dence in the medical terminology course.