The aim of this study is to enhance oral English proficiency of the local tour guides in Southern Thailand by using a web-application. The web application which served local needs was designed and used as a tool to promote teaching speaking skills for the tour guides’ training course. Quasi experimental research using one group pretestposttest design was employed. The result shows that after attending the training course, oral English proficiency of the local tour guides significantly increased. Most of the tour guides were satisfied with the course and teaching practices which promoted oral English proficiency that can be adapted for ESP classes and training courses in other parts of Thailand and beyond.