Reading comprehension is one of the four key language skills essential for academic success. It allows students to process and understand information effectively. However, many students struggle with reading, particularly in comprehending complex expository texts. To overcome these challenges, the use of metacognitive strategies—which involve planning, monitoring, and evaluating one's own thinking process—is considered a powerful approach as it encourages students to become self-regulated learners. In this research, the main problem is: “Is there any significant effect of applying metacognitive strategies on students’ expository reading comprehension?” and the objective is “to analyse the significant effect of the application of metacognitive strategies on student reading comprehension.” Based on the research problem and relevant theory, the hypotheses are the null hypothesis (Ho): There is no significant effect, and the alternative hypothesis (Ha): There is a significant effect of applying metacognitive strategies on students' expository reading comprehension.

The research employed a quantitative method with a quasi-experimental design. The sample consisted of 32 eleventh-grade students at SMKS Muhammadiyah Jember, who were divided into an experimental group and a control group. Data were collected using a reading comprehension test administered as a pre-test and a post-test. The research instrument was a multiple-choice test, focusing on identifying main ideas, text structure, and key information. The experimental group also utilized a reflection table to guide their metacognitive processes during the treatment phase.

The results, analyzed using the Wilcoxon Signed Rank Test, show a statistically significant improvement in the experimental group's post-test scores (Asymp. Sig. 2-tailed = 0.002), while the control group showed no significant change (Asymp. Sig. 2-tailed = 0.101). These findings confirm that metacognitive strategies, which enable students to actively plan, monitor, and evaluate their reading, lead to deeper comprehension and a significant positive effect on students’ reading achievement.