A very distinguished point of online marketing is that it can collect data about the consumers* shopping processes rather than the shopping results only. That is, it cannot only collect order data but also the browsing and shopping cart data. So far, the browsing records have been used to analyze the Web server traffic. However, regarding the analysis of shopping cart data, it has not been found in any marketing research yet. The purpose of this study is trying to verify the value of shopping cart data by examining whether it can improve the performance of the marketing communication decisions. According to Source-Message-Media-Receiver (SMMR) communication model, there are three important Web marketing communication decisions. These decisions are who are the target customers, what message should be communicated, and how to communicate. For each above marketing communication decision, in order to check whether the data from shopping cart can improve its performance, this research proposed an algorithm that integrates the shopping cart data into each decision process. Three hypotheses have been proposed in terms of the value of each new proposed algorithm. Three experiments have been implemented to test these hypotheses. The results reveal that the proposed algorithms can improve the performance of the marketing communications decisions. However, it is only a starting point to integrate the shopping cart data into the marketing research. As the online shopping becomes more popular, it is worthwhile to put more efforts to understand the details about the value of the online shopping cart data.