In this paper, magnetron sputtering from TaB 2 and Mo stoichiometric targets is used to prepare AlB 2 ternary Ta 1-xMo x B films. The films with various Mo contents were obtained by adjusting the Mo target powers. It was discovered that the contents of Mo have an obvious impact on the crystallinity and phase structure stability of Ta 1-xMo xB films. When x = 0.43, the (001) and (002) orientation is improved, while stabler AlB 2 structure is maintained simultaneously. While increasing x to 0.59, the films show amorphous structure. Meanwhile, as Mo contents rise, the hardness of films first decreases and then increases, eventually drops a lot. The Ta 1-xMo x B films with x = 0.44 exhibit the superhardness (H = 49.9 ± 1.5 GPa) and elastic modulus (E = 520 ± 4.7 GPa), which benefit from the structure of Transition-metal diboride (TMB 2 ) and solid solution strengthening effect. Alloying Mo can increase the Valence electron concentration (VEC) of films and therefore enhanced films toughness, higher fracture toughness (K IC = 1.13 MPa·m 1/2) and elasticity (85.805%) were achieved when x = 0.44, the films showed better ability to resist plastic deformation even in 500 gf load. In addition, the Ta 0.56Mo 0.44B films obtain higher wear resistance (4.5 × 10 −7 mm 3/Nm) in air, but excess Mo atoms lead to deterioration of mechanical properties (H = 25.0 GPa、E = 240.0 Gpa for Mo90). Ta 1-xMo xB ternary films with appropriate Mo content show a good potential as a hard protective coating.