This research was a quasi-experiment that examined the effects of CLIL in an educational context in Taiwan’s higher education. Two groups of first-year undergraduate students were involved. One (65 students) was taught with CLIL; the other (59), the conventional approach. Their knowledge of the content and learning attitudes (self-efficacy and motivation) were quantitatively compared through achievement tests and a questionnaire. A qualitative semi-structured survey asked both groups for their perspectives on and perceptions of the treatments. The quantitative results show that both approaches were significantly effective for improving students’ knowledge of the content of the target subject (literary text), but the EG outperformed the CG. Likewise, both groups had positive learning attitudes to their treatments, but the EG also outweighed the CG. Furthermore, the qualitative accounts generated diverse results, reflecting the underlying difference between the approaches but showing that both approaches were welcomed. However, the conventional method was more favored than CLIL, mostly because of the participants’ learning preferences or because of the learning patterns which they had formed over years of studying in the specific cultural-education system (i.e., that of Taiwan) chosen for the study.