Students' knowledge of academic vocabulary is a crucial aspect of learning English as a second or foreign language at the university level. Using academic vocabulary lists could be a valuable resource in teaching and learning vocabulary. This study measured the academic vocabulary size of Nepalese university students using Schmitt's (2010) Academic Vocabulary Level Test Version 2 as a data collection tool. The participants were 62 adult EFL students. The data were collected online via Google Forms. The results showed that the average academic vocabulary size of the students was 435 (76.3%) words out of 570 word-families in the academic vocabulary word list. The results also showed that the students had heterogeneous knowledge with varying degree of academic vocabulary achievement (M = 22.02, SD= 8.6 and Coefficient of Variation = 39.1%). The results of the study suggest that English education students at the university level in Nepal need explicit instruction, concentration, and practice to gain mastery over academic vocabulary with less variation of knowledge in their academic vocabulary achievement.