Abstract: Visitors' expenditure is the principal source of sports events to regional economic contribution,and it is also the key and difficult research issue.Much theoretical and empirical research on visitors' expenditure assessment was conducted,however,it is difficult to collect data and there are still a lot of disputes.This paper evaluates the economic impact of Asian Games from the perspective of visitors' expenditure.Research questions are:1) technically,how to obtain accurate data in order to getting net economic impact.2) To evaluate the economic impact of occasional sports events.Questionnaire survey is employed to collect the consumption data of visitors,I-O model is used to evaluate the indirect economic impact combined with statistic software including SPSS and Matlab.The result shows that 1) visitor classifications and number of visitors are specially studied,which gets partly net economic impact.Event visitor is the principal sources of economic impact of Asian Games.The number of event visitor only accounts for 32.56%;however,the economic impact generated by them reaches 61.39%.2) The number of Asian Games visitors is 722,074,and the economic impact generated is RMB 2,709,247,693,the average expenditure per person is RMB 1,688,the output multiplier is 2.22.Therefore,Compared with the new investment related Asian Games and the expectation of visitor expenditure,the economic impact caused by Asian Games visitors' expenditure is not outstanding.The conclusion is of some significance for pondering the passion for bidding mega-events.More attention should be paid to non-economic factors like city reconstruction,city image,and political influence.