WC-Co cemented carbides are extensively employed in aerospace, mining, and equipment manufacturing due to their outstanding hardness, wear resistance, and high-temperature mechanical performance, making them ideal for applying in demanding environments. However, with the continuous development in advanced manufacturing, these materials are increasingly challenged by the need for improved thermal stability, oxidation resistance, and thermo-mechanical reliability at elevated temperatures. A comprehensive overview of the factors affecting the high-temperature performance of WC-Co cemented carbides is provided, including alloy composition, high-temperature oxidation behavior, and mechanical degradation mechanisms. The influences of these factors on microstructural stability and performance are systematically analyzed. Meanwhile, recent advances and major strategies for enhancing high-temperature properties are discussed, including the optimization of heat treatment and sintering processes, grain refinement techniques, binder phase modification or replacement, and the incorporation of rare metal carbides. The application of molecular dynamics simulations in the study of WC-Co alloys is also briefly introduced.