In the field of advanced materials and energy harvesting, MXene has played a pivotal role in advancing the development of triboelectric nanogenerators (TENGs). This contribution is notable not only in terms of enhancing the performance of TENGs but also in expanding their application range. A comprehensive review of MXene materials is offered herein to delve into the significant impact of MXene on the growing efficiency of energy harvesting and widening application in areas ranging from energy harvesters to physiochemical sensors to self-powered intelligent systems. We begin with the fundamentals of MXene and TENGs, then highlight how MXene improves TENGs via its integration into the triboelectrification and electrode layers to increase the electronegativity, charge density, and introduce self-healing and stretchability. The discussion then extends to the modifications in MXene that boost the electrical output, stability, and collection efficiency of TENGs. Additionally, the review covers the diverse applications of MXene-based TENGs in extreme environments, respiratory monitoring, and multi-purpose devices, emphasizing its critical role in promoting TENGs to future self-powered intelligent systems.