The importance of vocabulary learning has been underlined in the field of English for Academic Purposes (EAP) because non-English majors who require reading English texts in their fields of study have to expand their English vocabulary knowledge much more efficiently than ordinary ESL/EFL learners. Since academic vocabulary instruction in Iranian universities is realized through the use of General English (GE) textbooks, the present study pursued a dual purpose of evaluating Iranian engineering undergraduates’ knowledge of academic vocabulary, as well as conducting a comparative corpus analysis of the academic vocabulary content of GE textbooks, electrical/electronic engineering Master’s Entrance Examinations, and authentic electrical and electronic engineering texts. The participants were 520 engineering students from ten universities. The corpora under study comprised a total of 1,180,000 running words. The results revealed an inadequacy of academic vocabulary knowledge among Iranian engineering undergraduates, as well as the fact that GE textbooks for engineering students do not have sufficient coverage of academic vocabulary as compared to M.S. examinations and authentic electronic engineering corpora. There was also insufficient correspondence between academic words in M.A. entrance exams and the authentic texts. تفاصيل المقالة