The present study sought to investigate the effectiveness of Content and Language Integrated Learning (CLIL) in enhancing Iranian aviation students' attitude and motivation in dealing with the highly specialized features of aviation English. To this end, 40 pilots studying at Mahan air in Tehran were randomly placed in the experimental (n = 20) and control (n = 20) groups. The study followed a pretest-posttest experimental design. The experimental group received instruction through CLIL. The control group were taught by a traditional approach. The analysis revealed that the experimental group performed better than the control group on the posttest. Interestingly the experimental group were highly motivated and had a positive perception about the effectiveness of CLIL activities that led them to be experienced in higher achievement of the language learning outcomes. Notably, the findings of the study suggest some important implications for course designers, and teachers who work in the area of teaching English for Occupational Purposes (EOP).