Purpose of the Study: The purpose of this research study was to study the relationship between critical thinking (CT) and academic achievement among secondary school students in a district of Gilgit-Baltistan.
 Methodology: Correlation design was applied to study the relationship between critical thinking and academic achievement. A sample of 400 students was selected through a convenient sampling technique to collect the data. Critical thinking was measured by applying an adapted tool (Sarigoz, 2012) and students’ scores in annual examinations were taken as academic achievement (York, Gibson & Rankin, 2015). Descriptive and inferential statistics were used to analyze the data.
 Main Findings: Findings of the study revealed that female students, rural school students, and science group students showed slightly higher critical thinking than male, urban, and arts group students. A markedly low positive relationship was found between critical thinking and academic achievement. The results were consistent with earlier studies having a positive relationship between these variables. There were also low and markedly low relationships found between constructs of critical thinking and academic achievement. Some results of this study were inconsistent with the earlier research based on the context of the students. The study revealed that there is a discrepancy in aligning critical thinking with academic achievement.
 Application of this study: The findings of the study help understand the relationship between critical thinking and academic achievement at the secondary level. It will surely assist the teachers in designing their classroom activities and modifications in teaching methodologies. It will boost the teachers to enhance the critical thinking of secondary school students.
 Novelty/Originality of this study: The study is original as not a single research study determined the relationship between critical thinking and academic achievement of secondary school students in the region of district Ghizar in Gilgit-Baltistan.