This thesis is on the basis of searching EWOM actively and attempt to treat the motivation of using discussion board, and how these motivations explain the influence of discussion board. Reviewing literatures, the thesis generalize the motivations of searching WOM actively and use product involvement to be situational variable in order to explore that the motivation and the consequence of using different discussion board. The thesis adopted bulletin board systems to be the research field, and distributed questionnaires. The research found that though consumers had different motivations of using discussion boards while facing products with diverse level of involvement, in fact, they normally take ¡§information searching¡¨ and ¡§recognition seeking¡¨ as the main motivations. Further, the explanatory power of these motivation factors on the consumers¡¦ behaviors changed by the discussion boards will differ with the product involvement.