Choosing further education after high school is one of the most important decisions during adolescence. However, not all individuals make such a decision easily and quickly, but they point out that they have difficulties making it. The aim of this study is to examine the relationship between individual characteristics of high school students and their career decision-making difficulties. The research was conducted in the form of an anonymous online survey. 174 students in their final year of high school planning to enroll in college participated in the survey. The individual characteristics examined in the research are five fundamental dimensions of personality, actively open-minded thinking, career adaptability, and perfectionism. The findings show that adolescents with higher neuroticism and negative perfectionism have more difficulties in making professional decisions, and adolescents higher in conscientiousness, openness to experience, career adaptability, and positive perfectionism face significantly fewer career decision-making difficulties. Furthermore, a hierarchical regression analysis was conducted to determine whether actively open-minded thinking, career adaptability, and perfectionism contribute to predicting career decision-making difficulties in addition to fundamental dimensions of personality. The results show a significant contribution to predicting the career decision-making difficulties of the mentioned predictors in addition to fundamental dimensions of personality. Such findings indicate that by acting on individual characteristics that are not relatively permanent, which is the case with fundamental dimensions of personality, timely interventions can reduce career decision-making difficulties among high school students.