The work aims to design multilayer Si-doped DLC film to improve the wear resistance and corrosion resistance of SUS304 stainless steel and extend the application scope. Three kinds of thick diamond-like carbon based films with different modulation ratios (1∶5, 1∶1, 4∶1) of 20.0, 34.9, and 41.6 μm were deposited on SUS304 stainless steel in the C2H2-SiH4 system by alternately depositing Six-DLC layer and Siy-DLC layer through plasma enhanced chemical vapor deposition (PECVD). The microstructure, mechanical properties, tribological properties wear scar composition, corrosion behavior and corrosion morphology of thick DLC films were characterized and analyzed by scanning electron microscope, atomic force microscope, Raman spectroscopy, nano-indentation tester, RST3 scratch tester, CSM tribometer and electrochemical station, respectively. The thick DLC films had dense microstructure, obvious strengthening effect and the highest hardness up to 13.8 GPa. The adhesion strength was in the range of 21 to 29 N. The friction coefficient of SUS304 stainless steel increased rapidly to 0.5 in the running stage, and still increased with the increase of the number of sliding times. The wear rate could not be measured by the profilometer after 1 h. The friction coefficient under low load and high load was between 0.05~0.2, and the wear rate was as low as 9.4×10-17 m3/(N?m). Electrochemical tests showed that SUS304 stainless steel corrosion potential was -0.49 V and corrosion current density was 1.46×10-6 A/cm2. Compared with stainless steel, the corrosion potential of the three thick DLC films shifted positively and the polarization resistance increased. The corrosion current density was reduced by up to three orders of magnitude. The application of thick DLC film can effectively reduce friction and wear and the corrosion tendency is significantly lower than that of stainless steel and has good corrosion resistance.