"Amazing Thailand” the slogan promoting country tourism industry achieves the accomplishment in global stage and successfully builds customer awareness of brand “Thailand”. Tourism is one of the significant industries that plays vital role for country revenue. With the huge amount of revenue could lure some people to think that establishing a travel agency is not too difficult to accomplish. However with the dynamic characteristic of industry nature and related factors: fierce competition, globalization, IT replacement and most important is consumer behavior which influence the dynamic changes in the tourism industry. These factors heat up the players that have to be ready and prepare for changes, even though the first mover advantage did not exist anymore upon the competition increase. This case study research provides an in-depth analysis of external and internal environment of tourism industry especially the travel agency in Thailand that use to be the first mover in the local area. Porter’ Five Force model is applied to analysis industry competitive force and Resource-Based View theory applies to create sustained competitive advantage for company. The suggestions are discussed to improve and assist company from struggling through revenue declination phase and stay strong in the competition through times.