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Ti/TiB2 multilayers with various modulation periods were prepared by magnetron sputtering system. An X-ray diffraction was used to characterize the phase and a scanning electron microscope was applied to observe the surface and fracture cross-sectional morphologies of multilayers. The mechanical properties of the multilayers such as nano-hardness, elastic modulus, adhesion and fracture toughness were evaluated with nanoindentation, universal micro materials tester and microhardness meter, respectively. The results show that the surface of multilayers is even, compact and smooth with clear nano-modulate structure and presents a good physical bonding between the coating and substrate. With the increase of the modulation periods of multilayers, the hardness and elastic modulus increases and attains the maximum value of 35.8 GPa and 349 GPa at the modulation period T=12. However, the fracture toughness of multilayers increases firstly and reaches maximum value (2.17 MPa?m1/2) at the modulation period T=6 and then decreases subsequently. Passivation effect occurs at the crack tip due to the insertion of Ti sub-layer in the multilayers, which leads to a path deflection of the crack propagation, as a result, improving the fracture toughness of the multilayers.