Lacking of competitive advantage (CA) becomes increasingly serious in 21 century. Researchers and practitioners pay great attention to exploring the resource of competitive advantage. Both Michael Porter and Woodruff have presented that customer value is the resource of competitive advantage in theory. But there is no em2 pirical resuts is rare in literature. The paper deals with this issue with two stages. Firstly , it is shown that customer loyalty is antecedent of competitive advantage based on the existing empirical study. Then , customer value is intro2 duced into the antecedent of behavior intention by reviewing the existing researches on antecedents of behavioral in2 tention. It is tested in this paper , by using the data of diesel motor in China , that customer value is the most impor2 tant antecedent of behavioral intention. Further , it is confirmed that customer value is the most important factor for any company to remain competitive advantage