The Cr/Cr-C gradient sublayer (total thickness of 550 nm) with different sublayer thickness was designed to improve the properties of DLC film on SUS304 stainless steel substrates by magnetron sputtering technique. The effects of sublayer thickness on the structure, adhesion strength, and tribological properties in the film was investigated. The results showed that there were Cr and Cr 3C 2 nanocrystals in the Cr C sublayer and Cr growth in (110) and (002) in the Cr sublayer. The sp 2C bond, surface roughness decreased first then increased with increasing thickness of the Cr sublayer. All films had internal stresses below 1.5 GPa, high adhesion strength and hardness. Especially, when the Cr/Cr-C sublayer thickness was 144/405 nm (sublayer thickness ratio about 1:2), the stress distribution was optimized, herein the S4 film had lower internal stress of 0.15 GPa, higher adhesion strength of 9.1 N, hardness of 9.1 GPa and elastic modulus of 63.6 GPa. Correspondingly, the S4 film had higher H/E and H 3/E 2 values, which resulted in more stable friction coefficient (0.2) and lower wear rate (1.8 × 10 −6 mm 3/Nm). The stress distribution of the film was calculated, and the maximum Hertz stress at the center of contact area (diameter was 3.058 × 10 −5 m) was 253,300 kPa, and it presented a decreasing trend along the diameter and depth. Furthermore, the Cr nanocrystals in the Cr C sublayer, not only facilitated crack energy dissipation and prevented crack propagation, but also diffused to the surface and underwent an oxidation reaction to generate Cr 2O 3 during the friction process, which improved tribological properties.