The integration of authentic materials into language teaching seems to attract an increasing interest from scholars and linguists thanks to their undeniable merits. However, a review and evaluation of the practical use of these sources is of great significance so as to gain an in-depth overview of their influences on language pedagogy in general and English language teaching at the tertiary level. Accordingly, this study was conducted to investigate the perceptions of instructors at a higher education institution on the effectiveness of authentic materials in teaching English for specific purposes (ESP), which requires various practical knowledge and skills. To this end, both quantitative and qualitative methods were employed. Nine ESP lecturers of the Foreign Languages Departmentwere invited to give responses to questionnaires and interviews. The findings reveal that mostinstructors had a positive attitude towards authentic materials and desired to integrate them into theESP curriculum despite their limited access to some undisclosed sources as well as time pressure inemploying these materials. This study also provides a basis for instructors to consider using moreauthentic materials in teaching ESP in the near future.