Reading plays important role in teaching and learning a second language as in reading, information is acquired and processed before learners can reach the final goal of English learning – communication. Extensive reading is a helpful way to develop students’ reading habits. A quasi-experimental study with one group pretest-posttest design was conducted in the Vietnamese educational context to investigate the effects of students’ use of metacognitive strategies on intermediate learners’ reading performance and attitudes. The results indicated positive changes in learners’ performance and attitudes, especially in higher-order thinking ability. Thirty-two participants from the convenient sampling method attended a 10-week reading course with metacognitive strategies embedded in extensive reading tasks. The scores from tests showed an improvement in reading comprehension ability and higher-order thinking application. The data from the questionnaire and semi-structured interview contributes to the positive attitudes toward students towards reading activities. This study has discovered the significant effects on the awareness of learners and afterwards cognition thinking. Learners have achieved a higher level of cognitive reading, critical reading and positive attitudes towards reading activity.