Objective To deposit ZrAlN coating with high hardness and good toughness. Methods ZrAlN thin films containing variable amounts of aluminum were deposited onto TC6 and Si wafers by magnetron sputtering Zr and Al target in an argon/nitrogen gas mixture. The microstructure and mechanical properties were characterized. The hardness ( H) , modulus of elasticity ( E) and fracture toughness ( KIC) of the film were tested. Results When the x of Zr1 -xAlxN films was 0. 05,0. 23,0. 47,0. 63, the corresponding hardness values were 24. 5, 40. 1, 17. 1, 19. 1 GPa, and the fracture toughness values were 1. 47, 3. 17, 1. 13, 1. 58 MPa· m^{-0. 5}. When x was 0. 05 and 0. 23, Al was dissolved in ZrN grains, forming NaCl face centered cubic structure. When x was 0. 47 and 0. 63, wurtzite HCP AlN second phase was formed. Conclusion The hardness and toughness of ZrAlN film were closely related with the phase structure. When Al was dissolved in ZrAlN, the hardness and toughness of ZrAlN were relatively high. When the solubility limit was exceeded, HCP AlN was formed, the hardness and toughness of ZrAlN were relatively low. In contrast, Zr0. 77Al0. 23 N had the highest hardness and toughness.