This current study investigated the correlation between the students' writing skills and each variable of metacognitive parameters, i.e. knowledge about cognition and regulation of cognition. We also examined the power of the correlation and its direction. We distributed Metacognitive Awareness Inventory for a comprehensive evaluation of the students' metacognitive awareness, and a writing rubric to assess the students' academic writing skills. Quantitative analysis by using Pearson Correlation test and Multiple Regression test were employed to check the correlation, and its strength and direction, respectively. The results demonstrated that there was a significant and unidirectional correlation between metacognition and writing skills. Furthermore, it was noted that knowledge about cognition and regulation of cognition together affect the English writing skills with an influence level of up to 41.7%, and each variable of the two parameters gave a great influence on the English writing skills up to 82, 2%. These findings indicated that a student with good metacognitive skills will have good self-regulated learning skills, which enable him to establish reasonable writing goals, plan and strategies, which as a consequence, will improve his writing skills. Pedagogical implication lies in the better understanding of metacognition that will help writing teachers to be supportive and encourage them to develop lesson plans which accommodate this notion.