Abstract: Hydrogenated DLC films were deposited on 304 stainless steel, GCr15 and 9Cr18 substrates by mid-frequency reactive magnetron sputtering. A ball-on-disk reciprocating tribometer was used to investigate the tribological properties of the films deposited on different substrates before and after different salt-spray exposure time. After that, the reasons leading to changes of tribological properties before and after salt spray test were discussed. The results show that after exposed to natural salt spray environment with different time, the corrosion resistance of different samples was accordance with their substrates. And after salt spray test, running-in period time of all films deposited on different substrates increased markedly especially the sample deposited on GCr15 substrate. What’s more, the wear life of film deposited on 304 stainless steel substrate before and after salt spray test nearly had no change but samples deposited onGCr15 and 9Cr18 substrates decreased approximately 50% due to corrosion.