Abstract: In order to understand the practice of adventure sports tourism, the various relationships of motivation, positive emotion and willingness are analyzed according to the investigations and empirical researches based on the marginal risk theory. The result shows that the internal motivation and exogenous atmosphere promote the emotions of tourists participation in tourism positively.Perceived risk plays a positive role in the path of "psychology-emotion" and "atmosphere-emotion".Positive emotions improve the attachment of tourists and spread their revisited wishes.