The study mainly aimed at constructing the indicators of professional competency for tour escort via Modified Delphi Method. The results appealed that dimensions and criterions of professional knowledge, tour leading techniques, and work attitude. Moreover, the criterions of "The capability of coping with emergences", "Using good time management to appropriately interpret attractions or spots to visitors", and "Visitors may feel as being respected while being gazed at sincerely and tenderly by the tour escort" are essential indicators of professional competency for a tour escort as considerably constructed in this study. According to above statements, the related results were specifically critical to develop the professional competencies of tour escort for travel service industry or youth corps; furthermore, it can be the basis of recruitment as well.