Abstract: Metacognitive reading strategies, which are documented to be beneficial to the EFL readers, have been constantly applied to many educational settings but not many in the Vietnamese high school contexts. The researcher, accordingly, introduced and trained how to use these strategies to 11th graders at a Vietnamese public high school. To check how these students perceived the benefits and challenges of their use of metacognitive reading strategies, the researcher carried out a survey using the questionnaire copies on 124 11th graders from four English reading classes. Based on the findings, it is indicated that the participants displayed their positive perceptions of using metacognitive strategies in their reading process; besides, their limited declarative, procedural, and conditional knowledge hindered their willingness and effectiveness in utilisation of these target strategies. Regarding their self-reported actual practice, problem-solving strategies were more favored than other groups namely global strategies and supporting strategies. The paper was concluded with some practical implications in the field of reading comprehension instruction.