Customers are the important strategic resources for the companies in E-commerce market, understanding customer’s consumption characteristics as soon as possible becomes more important for companies to win in a competitive online market. The paper tries to construct a model to represent the customer’s consumption characteristics based on a little information about this customer’s purchase behavior. In the model, the attributive combinations and their orderings of the products were found to reflect the customer’s purchase decision. An example arranged in the paper illustrates that the model can be a good tool for the companies to understand a customer or a group of similar customers’ consumption characteristics.