Over the last several decades, graduate students from engineering courses have faced a challenge of regular rejections in the work market despite their outstanding academic qualifications. In response to this challenge, many universities across the globe have introduced in their curricula the English for Specific Purposes (ESP) courses tailored to the need of engineering students. The present study evaluated the effectiveness of the ESP course for engineering students introduced at Dhofar University in Oman. The study participants were first- and second-year undergraduates from the Faculty of Engineering. The participants responded to a 26-item survey that addressed the course content and the changes in the students' English language proficiency. The results demonstrated that taking the ESP course had a positive impact on the course content, participants' vocabulary and grammar, as well as on their specific English language skills. The limitations of the study include a relatively small sample of participants and the self-reporting bias inherent in the use of a self-report methodology. Therefore, further research using more objective measures to evaluate the effectiveness and impact of ESP courses on English proficiency of engineering students would be needed.