The present study aimed at investigating the effect of CALL on intermediate EFL learners’ vocabulary learning and comparing it with traditional teaching method. To this end, a quasi-experimental design was used in which 80 students were chosen based on their performance in an Oxford Placement Test (OPT), and were randomly assigned to the experimental and control groups. Six reading comprehension passages consisting of 72 new words were selected from the book “504 essential words” and used as the pretest of the study. Then, the experimental group received twelve sessions of treatment which was teaching vocabulary through different tools in the computer such as related pictures, video, textual highlights, PowerPoint slides, or Narsis software while the control group received the traditional way of teaching such as providing oral pronunciation of words, explaining their parts of speech, and offering a direct translation of words in Persian. Afterward, both groups attended the post-test of vocabulary at the end of the study. The scores of learners in pretest and posttest were analyzed statistically via running independent T-test. The findings revealed that CALL instruction was more effective in enhancing learners’ vocabulary learning in comparison to the traditional vocabulary instruction. The findings indicated that the experimental group had a better performance than that of the control group, and the learners in the CALL group learned more vocabulary than the learners in the traditional group. The findings of this research have implications for teachers and learners as teachers can use CALL in EFL classes to help them be independent learners, and make vocabulary learning more attractive and enjoyable to learners. The findings can help material developers and syllabus designers to consider the importance of CALL while planning textbooks and materials.
