According to research findings, metacognition has been shown to have an essential role in education. As individuals are different,6 metacognitive knowledge cannot be the same for all learners. Learners need to be trained to improve their metacognition. Given this, the current study has examined the influence of scaffolding awareness and the use of metacognitive strategies during a strategy instruction program on the performance of Iranian EFL learners on IELTS writing task 2. To achieve this aim, using the Oxford Quick Placement Test (OQPT), eighty intermediate EFL learners (males and females) were selected from among 100 learners. They were randomly assigned to two groups of forty participants each as control and experimental groups. To benchmark the participants’ writing skills, an IELTS writing task 2 question was administered as the pretest. The experimental group received scaffolded metacognitive strategy instruction in their writing practices for four weeks, with 6 hours per week. The control group was instructed in traditional writing practices. The purpose was to promote the metacognitive awareness of the experimental group in performing the writing task. At the end of the treatment, another IELTS writing task 2 question was assigned as the posttest to measure the participants’ gain due to the treatment application. The independent and paired samples t-tests indicated that scaffolded metacognitive instruction effectively improved learners’ metacognitive awareness, which led to their improvement in writing skills. There was not any significant difference between males and females’ posttest mean scores.