It is remarkable that there are only a few studies that measures to what extent metacognitive and self-regulation skills affect students' academic achievements in the English lesson. This study is important for identifying the personal variables that have an impact on metacognitive and self-regulation skill and determining the relationship between these skills and the academic achievement in the English lesson. The purpose of the study is to see if there is a relationship between preparatory class students' metacognitive and self-regulation skills and their academic achievements in learning a language and to determine whether students' levels of metacognitive and self-regulation skills differ by certain variables. Descriptive survey method, one of the quantitative research models, was used in this study and data was collected by two scales. Students' grades in the first mid-term exam were used to determine their academic achievements. It was concluded that the students had high levels of self-regulation and metacognitive skills. Whereas students' self-regulation skills differed in favor of the female students, it was found that these skills did not differ by age, students' faculties, type of education, and type of graduation high school. A positive, significant relationship was revealed between students' self-regulation skills and academic achievements in the English lesson. While there was a relationship students' self-regulation skills and academic achievements in the English lesson, no significant relationship was found between their metacognitive skills and academic achievements. It was concluded that students' levels of metacognitive skills differed in favor of the female students but not by students' faculties, type of education, ages, and type of graduation high school.