This quantitative study aims to determine the correlation between conceptual comprehension and critical thinking ability in matrix subject of XI grades students in Tebing Tinggi District. The data collected through conceptual comprehension test and critical thinking test. The sample of this study are 62 students of XI IPA 1 SMA Negeri 1 Tebing Tinggi, SMA Negeri 2 Tebing, and SMA Negeri 3 Tebin…