Cp/AlSn composite coatings were deposited with 0.2 A to 0.8 A carbon target current on a bearing alloy and single crystal Si (100) wafer via unbalanced magnetron sputtering. X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were used to characterize the phase compositions, the morphologies and the chemical states of the deposited films, respectively. Results show that the composite coating has equiaxed crystal. The phases of Cp/AlSn films consist of homogeneously mixed aluminum, tin and carbon. The XPS spectrum of the deposited Cp/AlSn films confirms that aluminum and tin exist mainly in the form of pure metals, and carbon element is composed of sp2 and sp3 bonds, among which sp2 is the main bond