In recent years, airlines have developed business-to-business (B2B) web platforms specifically for direct business needs of travel agencies, providing the e-commerce functions of inquiry and trade. This study investigates the current travel agency usage of the B2B websites established by airlines in Taiwan and analyzes how the functions of these websites can be improved in the future. First, the functions of the B2B websites established by airlines in Taiwan are summarized. Questionnaires are administered to travel agents in Taiwan and descriptive statistical analysis is processed to understand the degree of importance of the various functions in these websites and the relationship between customer satisfaction and their usage frequency. Thus, the priority of improving the functions of airline websites is ranked. Next, factor analysis is used to extract dimensions for evaluating the functions of the websites. Analysis of variance is then used to investigate if any significant discrepancy exists in the use of airline website functions among various types of travel agencies and their employees. The results indicate there is a significant positive correlation between the degree of travel agencies, satisfaction with airlines, B2B websites and the frequency of the website they use. Different types of travel agencies and their employees have partially but significant perception differences on the degree of importance on various website functions, and they also have different website usage frequencies. This study finally provides related suggestions on how to improve these websites, making operation and trade between airlines and travel agencies faster and more convenient.