Many research results reveal that STEM learning can improve students' mathematical thinking skills. However, there are still few studies that comprehensively explain the impact of STEM learning on students' mathematical thinking skills that have been studied in a systematic literature review. Therefore, this study aims to examine the effect of using STEM learning on increasing students' mathematical thinking skills in terms of education level. To answer this objective, the Systematic Literature Review (SLR) method was used in this study. The stages of research with SLR in this study consist of (1) formulating the problem; (2) search for relevant literature; (3) identify the right type of research; (4) retrieve information from articles. The results of the findings indicate that the use of STEM learning is effective for improving students' mathematical thinking skills at various levels of education. In addition, the secondary school education level is the most effective level of education in using STEM learning.