Diamond-like carbon (DLC) films exhibit high hardness, high wear resistance and a low friction coefficient. They are extensively utilized in the mechanical, electronic and biomedical industries. Due to the gas barrier properties, it is used in the food industry also. To investigate the binding capacity of the DLC with the substrate and reduce the contamination for foods. The DLC (a-C: H) films on the glass slide and PET film were prepared successfully for different process parameters by plasma enhanced chemical vapor deposition (PECVD). In order to characterize the DLC film, the images of DLC was visualized by the atomic force microscope (AFM). The films were analyzed by Fourier transform infrared spectroscopy (RTIF). The contact angle and oxygen permeation analyzer (OTR) of the PET with and without the DLC coating were investigated experimentally. The results show that the DLC coating can improve the barriers and surface properties.