In order to handle the unstructured characteristics of Chinese Weibo data, the paper formulated a series of standards implying four dimensions of correlation, state, topics and emotion. The authors effectively extracted and purified the opinions or tendentiousness from huge amounts of user's data within Weibo, by means of the four key links, which are the sentiment dictionary, analysis of subjectivity, measurement of publisher's influence, and the establishment of sentiment index. While using this index system to the tourism market for an empirical analysis, it indicates that positive-sentiment Weibo articles would give vigorous impact on the next group of tourists. The precision of prediction will be greatly updated when applied with our Weibo positive-sentiment index in traditional time series analysis. By detecting attitude types with negative-sentiment Weibo data, the authors also can analyze the causes of tourists complain under different topics. The accuracy and efficiency of tourism management would boost using the state-of-art strategy derived from the index.