Word of mouth has been playing an essential role while consumers make their purchase decision since ever, and its diffusion is becoming much faster via the internet nowadays. Surfing the internet gathering information before making the purchase, the so-called ¡uWisdom of Crowds¡vshopping pattern is taking its shape and possibly going to become the main trend in the future. Thus, electronic word of mouth does play an important part during the process of consumers¡¦ decision making, and more and more consumers start to ponder what to believe on the internet. As a result, trust is becoming the key factor if the consumers can take electronic word of mouth into their consideration or not. This research discusses how message sideness appeal and emotion in electronic word of mouth affect consumers¡¦ trust under a positively framed message and a negative framed message. This research adopts experimental method, distributes questionnaire and analyze the data with SPSS12.0. The results present message sideness appeal and emotion have impacts on consumers¡¦ trust. Two-sided appeal can cause higher consumers¡¦ trust than one-sided appeal whether under a positively framed message or a negative framed message. Emotion also plays an important part between message sideness and consumers¡¦ trust during the process of diffusion of electronic word of mouth. The results can not only help the word-of-mouth senders to develop an appropriate writing pattern to make electronic word of mouth more credible and effective, but also provide the business a brand-new point of view and some practical suggestions to develop a new marketing strategy.