Vocabulary is a fundamental requirement of language acquisition, and its competence enables independent reading and effective language acquisition. Effective language use requires adequate level of vocabulary knowledge; therefore, efforts must be made to identify students’ vocabulary base for greater efficiency and competency in the language. Students with limited vocabulary size may fail to comprehend the contents of the reading materials and their learning may be impaired. This study had aimed to address this concern and sets out to examine the vocabulary knowledge, i.e. in terms of vocabulary level and size of undergraduates at a private university in Malaysia, where English is the medium of instruction. 120 first year undergraduates from three academic programs, who participated in this study, sat for the Nation and Laufer’s (1999), Version A of Productive Vocabulary Levels Test, which is recommended and used for diagnostic purposes. The findings show that almost none of the students have acquired the vocabulary required at UWL, and most of them managed to acquire only a 2000 word level at Level A. At UWL, a larger proportion fell on the lower scale, implicating that their vocabulary knowledge is insufficient to cope with the reading text and possibly with the studies at the university.