Traditional learning, where a teacher teaches in a classroom and the students only listen, has several weaknesses. Some of the weaknesses are students have the tendency to be passive and less critical in the process of teaching and learning. The objective of this research is to analyze the effect of applying the problem based learning to students' critical thinking and metacognitive. This research was conducted using quantitative approach and experiment method. The subjects of this research were 28 grade XII students at High School "XYZ" Makassar. The results of this study show that the problem based learning method is able to increase students' critical thinking and metacognitive abilities.