This study aims to assess the English language outcome of Content-Based Instruction (CBI) among EFL learners of English at the tertiary level of Bangladesh and the problems involved in this process, where a group of students and teachers (existing) of English department were the focus of the study. To conduct this study, a mixed-method approach was applied where research instruments such as questionnaire and classroom observation were used. In total, 279 (students=260, teachers=19) respon dents participated in the survey questionnaires and classroom observations. The findings of this study suggested that though teachers and students prefer the CBI approach, some drawbacks were found in this learning process. Keywords: Content-Based Instruction, Tertiary Level Learners of Bangladesh, EFL context