The work aims to improve the service life of GCr15 and W18Cr4V steel by preparing hard wear resistant nano-films on GCr15 bearing steel and W18Cr4V high-speed steel substrate. With argon as working gas and nitrogen as reaction gas, the high-quality wear resistant films were prepared on two common steel substrates by taking advantage of DC reactive magnetron sputtering by using a group of optimal parameters obtained by our research team from repeated tests. XRF, XRD, AFM and SEM were employed to study the structure characteristics including chemical composition, surface morphology of the films. The frictional wear properties of the films were investigated by using pin disc friction and wear testing machine. The chemical compositions of films on two groups of steel substrates were very similar, Ti and Al element content ratio was 1:1, the films were mainly composed of AlN, TiN and TiAlN, and had a preferential orientation in the (111) direction. The average grain size of films were 24.15 nm and 28.32 nm respectively. The films presented island growth, average roughness of the surface was 15.8 nm and 17.6 nm respectively while hardness was less than 2500HV. The friction coefficients were 0.5 and 0.4 respectively and abrasion loss of the films were 89 μg and 56 μg respectively. The structure of films is composed of hard ceramic phase and is provided with small average grain size and better wear-resisting effect due to stable friction coefficient and minor wear loss.