Tribological properties of Al₁₉Fe_20-xCo_20-xNi₄₁Mo_2x (x=0, 1, 2, 3, 4, 5) eutectic high-entropy alloys (EHEAs) were investigated in this research. Results show that EHEAs with trace Mo addition can form the face-centered cubic (fcc)+B2 eutectic microstructure, whereas EHEAs with relatively higher Mo content can form fcc+B2+μ dendritic microstructure. Mo element is beneficial to the strength enhancement of L1₂ phase and the ductility improvement of B2 phase. However, with increasing the Mo content to x>2, the resultant Mo-rich μ phase degrades the strength and plasticity of EHEAs. Al₁₉Fe₁₈Co₁₈Ni₄₁Mo₄ EHEA has the optimal combination of high strength and high ductility. Increasing Mo content can improve the oxidation resistance of EHEAs. With increasing the Mo content, EHEA forms a tribo-oxide layer with improved oxidation resistance during sliding process, and the friction coefficient is monotonically decreased. This research provides guidance for the investigation of tribological properties of Al₁₉Fe_20-xCo_20-xNi₄₁Mo_2x EHEAs.