The CoCrFeNiMoₓ high-entropy alloy (HEA) coatings face limitations in high-temperature applications due to two key challenges: (1) an unclear relationship between elemental composition and elevated-temperature tribological behavior, and (2) the high cost of raw materials. To address these limitations, this study fabricated CoCrFeNiMoₓ (x = 0, 0.2, 0.5, 1) HEA coatings using Extreme High-Speed Laser Cladding (EHLA) and investigated the effect of Mo content on microstructure evolution and high-temperature tribological properties. The coatings primarily consist of an FCC solid-solution phase and a hard σ phase. The addition of Mo induces significant lattice distortion and promotes σ phase formation. Increasing the Mo content enhances microhardness from 190 HV 0.2 to 600 HV 0.2. This improvement is attributed to the synergistic effects of lattice distortion, fine-grain strengthening, and σ phase reinforcement. Furthermore, Mo enhances the formation and adhesion of protective oxide glaze layers at temperatures above 400 °C, significantly improving tribological performance. Notably, the wear rate of the Mo₁ coating at 800 °C was only 1/12 that of the Mo₀ coating. The comparison of wear track microhardness before and after high temperature friction reveals that the formation of the oxide glaze layer significantly increases the microhardness, effectively reducing the wear rate of the coating at elevated temperatures.