As a key marketing tool, online sales promotion has been widely used by online retailers to increase sales of products and brands. Most previous researches on online sales promotion have ignored the effect of consumers' psychological factors and the heterogeneity of product and consumers. The purpose of this study is to examine the role of psychological distance and involvement on consumers' buying behavior in large online promotion activities. The research model was examined using empirical analysis of data obtained from consumer surveys after the Double 11 promotion. Our results indicate that temporal distance has positive impact on purchase decision of high involvement products, while having negative impact on purchase decision of low involvement products. Social distance has negative impact on consumers' purchase decision. Temporal distance is positively associated with consumers' purchase-decision involvement, and then purchase-decision involvement positively impacts consumers' total consumption. Social distance has no impact on consumers' purchase decision involvement. These findings not only advance the understanding of the role of psychological distance and involvement in online sales promotion but also offer implications regarding strategies that online retailers can employ to publish their promotions at different times and encourage consumers more to share promotional information among their friends. social target; the probability dimension is based on the perceived (lack of) probability of a hypothetical event happening [62].Psychological distance has been applied to various areas of consumer research, including goal pursuit [19], product evaluation [33], decision creativity [49], consideration-set formation [22] and decision-making [53]. Kim et al. (2008) suggest that most of CLT research has concentrate only on one dimension of psychological distance [34]. Accordingly, some recent research has examined the influence of multiple dimensions. Chandran and Menon (2004) studies the interaction which in consumers' judgment of risk between temporal distance and social distance [8]. From the perspective of social and temporal distance, Bornemann and Homburg (2011) examine the relationship between perceived quality and price [5]. Zhao and Xie (2011) explore the interplay of social and temporal distance on consumers' responses to recommendation systems [65].H1b: When purchasing low involvement products, the temporal distance is negatively related to consumers' purchase decision in large online promotion activities.CLT originated with the temporal perspective and has recently been extended to other dimensions such as social distance. The difference between self and others, similar and dissimilar others, or in-group and out-group members are all the examples of social distance [57]. Prior research has shown when making decisions for dissimilar others, consumers trend to highlight the core and main properties; while for similar others, consumers trend to concern the affiliated and secondary properties [57], [65]....