Co 20 Cr 20 Cu 20 Fe 20 Ni 20 (at.%) (Al-0) and Al 33.35 Co 13.33 Cr 13.33 Cu 13.33 Fe 13.33 Ni 13.33 (at.%) (Al-2.5) high-entropy alloy films with thicknesses less than 500nm were successfully fabricated by sputter technique using alloy targets. Their microstructures are characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectrometer, transmission electron microscopy and nanoindentation techniques. It is found that compositions for both films are uniformly in depth. The both as-deposited films are composed of nanometer-sized grains with serious lattice distortion. The as-deposited Al-2.5 film, having a hardness of 15.4GPa and reduced Young’s modulus of 203.8GPa, exhibits a body-centered cubic structure and remains stable up to 873K for 20min whereas the as-deposited Al-0 film, having a hardness of 6.3GPa and reduced Young’s modulus of 87.9GPa, exhibits a face-centered cubic structure and remains up to 773K for 20min. It seems that due to high temperature structure stability and high hardness, the Al-2.5 film could be used as a potential coating material on high-temperature Ni-based alloys.