Abstract-This study investigated the reading comprehension questions in EFL textbooks and their appropriateness to learners' levels. The data for the study were collected from four elementary and advanced level EFL textbooks containing 44 chapters altogether. A checklist was designed based on Bloom's Taxonomy of reading comprehension questions to record the cognitive levels of the questions collected from the reading comprehension sections of the mentioned textbooks. To assess the significance of difference between each kind of the comprehension questions in elementary and advanced level textbooks, the Mann-Whitney U test was used. Results indicated that there are significant differences between the two proficiency levels in terms of question types in all categories except analysis and synthesis. To assess the overall proportions of question types in the textbooks and to see if they are different from each other, a Kruskal-Wallis and the follow up Mann-Whitney U tests were used which revealed significant differences between some pairs of categories of question types. It is believed that the results of this study can be useful to textbook writers and EFL teachers.