Abstract: The value of online customer reviews have been recognized by customer and online retailers and research on the helpfulness of the review have become the emerging fields. From the start of reducing the risk of consumer decision-making,this study defined the conception of helpfulness of the customer reviews based on the conception of perceived diagnosticity and built a model of the helpfulness factors of online customer reviews. Based on the theory of communication and persuasion,revicw rates,review length,percent of helpfulness and experience of using the Internet arc the important factors affecting helpfulness of the review. Product type moderates the helpfulness of the review.

Key words: Online customer reviews, Perceived diagnosticity, Helpfulness, Search goods, Experience goods