The purpose of this study is to investigate the effect of achievement goal orientation on Exercise Flow and perceived performance and provide basic data that will help athletes to improve their performance level. For this study, a questionnaire survey was conducted on 230 of the athletes who participated in the 29th Yongin University Present Flag National Taekwondo Competitions, which were registered with the Korea Taekwondo Association in 2019, and data from 203 participants were used in the final analysis. Frequency analysis, factor analysis, reliability verification, t-test, one way ANOVA, correlation analysis, and multiple regression analysis were conducted using the SPSS 25.0 program as data processing methods. The results of this study are as follows. First, out of the demographic characteristics of the high school taekwondo competition players, gender showed significant differences and grades showed no significant difference. Out of athletic career, perceived performance showed significant differences, and task goal orientation, exercise commitment, and perceived performance, which are sub-factors of achievement goal orientation out of prize-winning career, showed significant differences. Second, among the sub-factors of the achievement goal orientation of the high school taekwondo competition players, task goal orientation affected cognitive commitment among the sub-factors of Exercise Flow but ego goal orientation did not affect Exercise Flow. Third, among the sub-factors of the achievement goal orientation, task goal orientation affected perceived performance. Fourth, Exercise Flow affected perceived performance. Therefore, it is considered that when instructors teach high school taekwondo competition players or when the players undergo training by themselves to improve their performance, the players' psychological training is important although physical training is also important and that higher performance can be achieved when training for achievement goal orientation and Exercise Flow out of psychological training is also undergone. In-depth follow-up studies on the effect of achievement goal orientation of taekowndo players on their Exercise Flow and performance are required and through the studies, practical psychological training models for improvement of performance should be developed.