The main objective of this study was to determine whether hope for success mediates the relationship between personality and goal orientation in high performance and recreational athletes. The cross-sectional study included 289 high performance and recreational athletes of various sports (age: M = 20.34, SD = 1.86). To examine personality, we used the Big Five IPIP-BFM-20 questionnaire. To assess hope for success, we used the Hope for Success Questionnaire. The Task and Ego Orientation in Sport Questionnaire (TEOSQ) was employed to examine goal orientation. Hope for success significantly mediates the relationships between conscientiousness, extraversion, emotional stability, intellect, and task goal orientation in sport. Higher levels of these personality traits are related to athletes’ higher hope for success, which, in turn, is positively related to their task orientation. Personality traits may underpin the hope for success that develops from childhood. This, in turn, appears to be an important component on which, combined with the positive interaction and support from coaches, a task goal orientation beneficial to sport can be shaped in athletes.