Abstract: Many prior studies have indicated that Electronic word-of-mouth(eWOM)as an important information source influences consumers' attitudes towards products and their purchase intentions. However, there is little study investigating the distinctions between different eWOM platforms and their impacts on consumers' decision-making. The influence of different features between e-commerce eWOM(EC-eWOM)and social media eWOM(SM-eWOM)on consumers' perceived eWOM credibility was verified. A mixed design of experiment for 2(eWOM platforms)×2(product-related risks) conditions and a questionnaire survey were applied to investigate the question. Software SmartPLS 2.0 was used to calculate the path coefficient and the significance of latent variables. The results indicated that both tie strength and volume of social cues in social media were greater than those in e-commerce websites. For social media, tie strength between eWOM publishers and recipients and the volume of social cues positively influenced perceived eWOM credibility. Perceived eWOM credibility positively influenced the purchase intention. For products with low risks, EC-eWOM was perceived to be more credible. Thus, e-commerce website designers should add interactive functions to the product comment area to enhance communications between reviewers and potential consumers, and they can cooperate with social media managers to encourage consumers to share their shopping experiences and product information on social media.