Chinese tourist market is mainly constituted of domestic tourists. Rationalization on regional tourism organization can be reached through rational analysis on spatial structure of tourism origin. Based on the analysis of tourism market, origins on domestic tourism market of Xi'an can be divided by different provinces. By using three years' tourism statistics (1995,1998,2001), different periods of radius of tourism abstraction and index of spatial affinity are calculated with the formula of "Central Destination Standard Distance", the results are compared and the regulation of distance attenuation of domestic tourism market is summarized, the trend of diversification of tourism abstraction in Xi'an is forecasted. Meanwhile, 2000 questionnaires are sent out to investigate the visitors in 10 scenic spots. 1780 valid responses are analyzed, the behavioral characteristics of domestic tourists in choosing scenic spots around Xi'an are found out, and the mode of space selecting is put forward. Conception of big tourism circle of Xi'an is established, and the boundary of circle is ascertained. The location, the condition of resource and the standard of utilities in Xi'an is considered, and the principle of big tourism circle development is proposed. Finally, five conclusions are summarized: 1) Distribution of domestic tourism origin is dispersing gradually; 2) current domestic tourism origin of Xi'an is mainly constituted of circumjacent provinces and provinces in eastern China, this phenomenon will remain in the future; 3) domestic tourism market of Xi'an can develop persistently via regional cooperation; 4) the preference of human tourism abstraction is apparent for tourists from other provinces; and 5) integrated development of tourism in Xi'an and Xianyang is the primary step to construct the big tourism circle of Xi'an.