Project-Based Learning is an approach that is significantly different from the conventional English Language Teaching method. PBL has been advocated as an effective instruction that promotes the simultaneous acquisition of language, content, and 21st-century skills to EFL (English as a foreign language) and ESL context. In this study researcher’s attempt is to integrate PBL (Project-Based Learning) approach, which incorporates authentic, learning by doing, problem-solving, critical thinking and team working skills with ESP (English for specific purposes) courses. The study aimed to investigate whether the PBL projects assist EFL learners in acquiring department related literature and information in the English language and the effect of project work on learners’ ESP course academic achievement. The study was conducted at Tishk International University, formerly known as Ishik University, in Iraq-Kurdistan Region with 2 Engineering (Architectural and Civil engineering) and Business and Management departments’ students. A mixed-method approach was designed to make the authentic interpretation of gained results. Quantitative and Qualitative instruments were utilized to probe the effect of PBL in the ESP course of undergraduate Iraqi EFL learners. The findings of this study reveal that PBL had a significant positive effect on acquiring department-related vocabulary and information in English as well as learners’ ESP course academic achievement showed statistically significant increment.