Ti3C2Tx MXene, a revolutionary 2D material, has shown bright prospects in various fields, including energy conversion and storage, electronic devices, electromagnetic interference shielding, catalysis, biomedicine etc. The large specific surface area, high electrical conductivity, abundant surface terminations, and the highest stiffness among all solution-processed 2D materials of Ti3C2Tx MXene make it a rising star in polymer composites. Not only have Ti3C2Tx MXene-based polymer composites come into prominence in sensing, energy storage, and photothermal conversion fields as is widely known, but they have also shown great potential in corrosion and tribology fields. Hence, this critical review provides a comprehensive overview of the synthesis strategies, me-chanical, and tribological properties of Ti3C2Tx MXene and the recent advances of Ti3C2Tx MXene reinforced polymer composites in corrosion and tribology aspects. The challenges of Ti3C2Tx-based polymer composites faced in corrosion and tribology fields are also summarized. This analysis of Ti3C2Tx-based polymer composites will stimulate a booming field including but not limited to corrosion and tribology, bringing Ti3C2Tx MXene from lab to engineering application.