ABSTRACT As group buying has made rapid developing in recent years, especially in mainland China, there have been many investigations into group buying. Existing researches of group buying focus their attention on the efficacy of group buying model, group buying discount and price mechanism, the comparison of the group buying auction and so on. This thesis intends to find the consumers’ motives to join in the group buying and makes recommendations based on Chinese market, so companies can use and apply group buying as a new promotion instrument. The author uses in-depth interview to identify the direction of the study problems, and uses questionnaire to do the quantitative research. The reliability and validity of the questionnaires are tested. Multiple regressions are used to test the research model. The study shows that consumers’ shopping orientation positively influences their attitude toward group buying. Consumers’ perceived risk has negative influence toward attitude, but do not have significance. Consumers’ trust to the initiator positively influences their attitude toward group buying, but does not significantly influence consumers’ perceived risk. Attitude positively influences participation intention. How to use group buying model to make more business opportunities is the issues faced by more and more companies. Managerial implications are given based on the theoretical results. Keywords: Group buying, mainland China, consumers’ motives, in-depth interview, questionnaire, regression.