Extended Reality (XR), encompassing Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR), has emerged as a pivotal enabler of immersive learning and a key driver of instructional innovation in STEM higher education. This study aims to systematically examine the pathways through which XR supports experiential and situated learning, as well as its educational effectiveness in the context of STEM higher education. Following the PRISMA systematic review methodology, this study conducted a comprehensive search of empirical studies published between January 1, 2020, and May 31, 2025, using the Web of Science and Scopus databases. A total of 32 eligible studies were included in the final analysis. The findings reveal that Experiential Learning Theory and Embodied Cognition Theory provide the theoretical foundations for XR-supported immersive learning. From the perspective of technical support, VR is the most widely applied in supporting experiential and situated learning, followed by AR, while the application of MR remains limited. XR demonstrates significant positive impacts on students’ competencies, academic performance, knowledge integration, learning motivation, and classroom engagement. However, the review also identifies some challenges to implementing the XR, including high equipment and development costs, insufficient technical support, and limited digital competencies among instructors, which constrain sustainable integration and large-scale adoption in STEM higher education.