In order to improve the task performance of tour guides, this study explored the mediating mechanism and boundary conditions of the influence of customer orientation on task performance of tour guides, and constructed a relationship model among customer orientation, adaptive selling, task performance, and social support. This study uses the nonparametric percentile bootstrapping method with deviation correction by AMOS software and SPSS software to analyze the data. The results showed that customer orientation positively affected task performance of tour guides, and social support strengthened this relationship; adaptive selling played a full mediating role between customer orientation and task performance of tour guides. That is to say, travel agencies can improve the task performance of tour guides by creating a supportive climate, promoting a customer-oriented culture, and strengthening the training about adaptive selling ability.