This study aims to analyze the strengthening of 21st century competencies through Islamic Religious Education (PAI) in Madrasah Ibtidaiyah (MI) students using the Systematic Literature Review (SLR) method. The 21st century competencies studied include critical thinking skills, creativity, communication, and collaboration (4C). The SLR method is carried out through the stages of planning, literature search, article selection, data analysis, and synthesis of findings from various relevant scientific journals in the 2020–2025 range. The results of the study show that PAI learning in MI plays an important role in developing 21st century competencies. Critical thinking is developed through the discussion and analysis of Islamic issues, creativity through projects such as the creation of Islamic learning media, communication through presentations and group discussions, and collaboration through group work-based learning. In addition, the most effective learning models in supporting the strengthening of these competencies are Project-Based Learning (PjBL), Problem-Based Learning (PBL), and the use of digital technology. However, there are still several obstacles in its implementation, such as limited technological facilities, uneven ability of teachers in the use of digital media, and the dominance of conventional learning methods. Therefore, learning innovations and teacher competency improvement are needed so that strengthening 21st century competencies through PAI can run more optimally. Overall, Islamic Religious Education not only plays a role in shaping the religious character of students, but also becomes a strategic means in developing 21st century skills needed in the era of globalization.