It cannot be denied that language learners with poor vocabulary and fluency will have serious difficulties with comprehension. However, according to Cain & Oakhill (2006), learners with adequate word-reading ability and fluency can still find it difficult to understand a reading text, especially in long academic texts due to their poor familiarity with the academic subject matters and lack of metacognitive strategies. With the aim of enhancing reading comprehension skills in EFL learners, this action research was conducted with a group of 35 students at level B2 from University of Engineering and Technology, Vietnam National University to find out the effects of reading reflections on developing their metacognitive skills throughout a 15-week course. From the second week onwards, a reading reflection assignment was given to encourage the students to reflect metacognitively on what they had chosen to read based on the teacher’s assigned topic. In the reading assignment, students were required to summarize the text they had chosen, what new things they had learnt from it and what they thought about it. The findings revealed that after 14 weeks, the regularly assigned reading reflections proved its power in improving the learners’ language proficiency as well as fostering their metacognitive skills needed for academic reading comprehension. 100% of the surveyed participants became much more familiar with a wide range of academic subject matters and found themselves faster and better at understanding and making inferences from academic texts.