This study aims to find out the effect of computer based teaching activities on the academic achievement and retention of technical programme Students of Computer Programming on Vocational Foreign Language in Computer Technologies Department. The study was conducted in Vocational School of Technical Science in Suleyman Demirel University with 30 students of computer programming. The experimental group (15 students) was taught with computer assisted instructional software and the control group (15 students) was taught with traditional methods. Achievement test was developed to measure the success of second class students of Vocational Foreign Language lesson was used as pretest, posttest and retention test. As a consequence, it is seemed that the application of computer assisted instructional methods used Vocational Foreign Language lesson is more effective than traditional instructional methods in terms of students' academic achievement and retention. (C) 2015 Published by Elsevier Ltd.