This study examined the differences among high، mid and low ambiguity tolerance groups in their reading comprehension ability and their metacognitive awareness of reading strategies. To this end، 123 first-year college students majoring in Engineering with an age range of 19-25 were stratified into three groups of high، mid and low ambiguity tolerance to participate in the study. They took part in the Nelson test of proficiency and a reading comprehension test and also filled out two questionnaires: the Metacognitive Awareness of Reading Strategies Inventory، and the Tolerance of Ambiguity Scale. The results showed significant differences between Low and High groups. That is، high ambiguity tolerance students scored higher on reading comprehension test، displayed higher metacognitive awareness of reading strategies، and showed higher perceived use of Global and Problem-Solving metacognitive reading strategies. However، no significant differences were found between the middle group and the other two groups in these variables. Also، no significant difference was found in the use of Supportive strategies among these three groups. The findings are interpreted to have implications for syllabus designers and EFL teachers.
