In the wake of globalization of business and stable development of world economics as well, peoples traveling around the world become more and more heavily reliant on airline and travel agent¡¦s assistance. So, the copetition relationship between airlines and travel agents becomes one of very important subjects. In this study, a case of Cathay Pacific Airways in regard to the copetition relationship between airlines and travel agent is discussed. The purpose of this study is, through the interviews, questionnaires, investigation, and LISERL model (Joreskog, 1973), to analyze the results, to understand both influence and performance which the copetition relationship between airlines and travel agents will lead to, and to propose practical suggestions to the airlines industry. The conclusion of the study is listed as follows: 1.The scale of travel agents is statistically positively related to airlines performance, and positively related to sale behavior difference between airlines and travel agents. 2.The elements of the product service and the content of contract can obviously affect the customer relationship, and also affect performance of airlines and travel agents. 3.In a long term, airlines and travel agents would rather to be in cooperation than to be in competition, in order to maintain good win-win relationship to run lucrative business.