Abstract:Online purchase brings more ambivalence to customers’ attitude due to the fact that customers can not observe the products directly by themselves before they pay. This study conducted two lab experiments with a 2 (high ambivalence vs. low ambivalence) ×2 (subjective word-of-mouth vs. objective word-of-mouth) design to examine how the ambivalence of attitudes of online shopping customers affects their word-of-mouth processing efforts and the persuasive power of positive reviews to them. It is found that online customers with higher ambivalence in their initial attitude have higher information sufficiency threshold, and adopt more systematic processing with more effort, but are more reluctant to reduce their ambivalence facing positive reviews. It is also found that objective word-of-mouth has more power to reduce customers’ ambivalence than subjective word-of-mouth does, and online customers with higher ambivalent attitude are more sensitive to the subjective attributes of reviews. The findings remind the B2C businesses to find ways to guide customers to comment in the more objective way as well as accumulating positive reviews.