In this thesis, Diamond-like Carbon (DLC) films on metal surface were deposited by radio frequency plasma-enhanced chemical vapor deposition (RF-PECVD). The properties of films were detected by Raman spectroscopy, FTIR, XPS, SEM, AFM, scratch test, friction test, and indentation test. The results show that the DLC film can be deposited on metals by RF plasma. The deposition rate increased with the deposition time but decreasing in extended period. Due to the initial force between film and substrates, the adhesion of DLC film on substrates has a problem. Films are cracked and peeled off easily from the substrates. Besides that the films are not wearability. To solve such problem Ti and TiN gradient layers are prepared by electron beam evaporated deposition and magnetron controlled sputtering method before DLC film deposition. The results indicate that adhesion and the wearability of DLC films are significantly increased. Through analysis of Raman spectroscopy, FTIR, and measurement of indentation test, it notices that the ratio of methane in the deposition plays important role in DLC structure and properties where the more sp3 concentration the harder film.