Abstract: Linear polarazation method is used to select the best surface treatment technique for aluminium and its alloys in 21 kinds of cerium contained solution. The effects of the CeCl₃ concentration, expose time, the solution temperature and pH on the corrosion resistance of the cerium rich coatings are discussed. The electrochemical measurement result shows that the corrosion resistance of aluminium alloy is significiantly improved after cerium rich coating is formed.Both cathodic and anodic corrosion processes are restrained. The surface analysis shows that the film consists of oxygen, cerium and aluminium.