Recent developments in computational and corpus linguistics have yielded more refined tools that can analyze a text more reliably according to various textual features. Using these automated tools, this study analyzed reading comprehension passages of academic nature, sampled from TOEFL and TEPS and compared them with the focus on their syntactic and lexical complexity. By testing whether there is a significant difference between the observed values obtained on each of several textual characteristics, the current study examines the comparability of these texts across TOEFL　PBT vs. TOEFL iBT and　TOEFL iBT　vs. TEPS. Based on the results of the comparison, the study discusses the probable reasons for the differences between reading passages as well as the necessity of conducting these studies when using different reading comprehension tests interchangeably. (Seoul National University)