This paper is a corpus-based, comparative study of the college entrance English exams in Korea, China, and Japan, and its main goal is to analyze the English vocabulary used in these English exams to evaluate how appropriate they are for measuring prospective college students` English proficiency for higher education. The results indicate that the Korean English exam shows the highest vocabulary level in all aspects, including vocabulary size and overall vocabulary level. In particular, considering the lexical coverage of college-level English vocabulary, the Korean English exam can be considered more appropriate for measuring students` English proficiency than the Chinese or Japanese English exam. Despite this encouraging finding concerning the relative status of the three countries` national exams, however, we are doubtful about the appropriateness of the Korean English exam in achieving the important evaluative goal, mainly due to its low coverage of college-level vocabulary.