The online shopping market is more and more prosperous, female consumers are the main markets. We use an experiment design to examine the research, adopts three factors design: 2 (high reference price, low reference price) x3 (promotion situations: time limited, amount limited, time and amount limited) x3 (the perceived risk degree of the products: high risk, middle risk, low risk products) experiment design. Taking the female students of Tatung University as the experimental subjects, examining while female are shopping online, how does perceived risk moderate the reference price and the promotion situations on the purchasing intention effect. Examining it with three pretests and a formal experiment, the results indicate that there is moderating effect on the perceived risk.