Diamond-like carbon (DLC) films have many advantages,such as high hardness, low friction coefficient, and high chemical stability. They have been widely used for improving the surface hardness and wear resistance of light alloys. To improve the mechanical properties of 2024 aluminum alloy, a kind of DLC film was deposited on the surface of 2024 aluminum alloy by plasma-enhanced chemical vapor deposition technique.?The effects of acetylene gas on the microstructure, hardness, wear resistance and adhesion of DLC film were investigated by field emission scanning electron microscopy, nano-indentation, friction-wear test. The results indicate that the thickness of the?DLC film increased gradually with increasing the proportion of acetylene. There is an obvious transition layer between the DLC film and matrix. When the ratio of argon to acetylene is 1:3, the hardness of the DLC film was enhanced significantly because of the changes in the content of sp3 and sp2 bonds within the film. At the same time, the coefficient friction of the DLC film was reduced. This work provides an experimental and theoretical basis for improving the mechanical properties and enhancing durability of aluminum alloys.