Assessing the development of skills that ensure personal mental toughness in adolescence is important because the increasing autonomy and socialization of adolescents during adolescence inevitably creates the conditions for the emergence of an increasing number of external stressors. Paradoxically, adolescents' confidence in their ability to cope with external stressors decreases during adolescence, which may lead to poorer sport performance in adolescent athletes. The aim of this study was to determine and analyze mental toughness skills in the cadet and junior age groups of young basketball players. An additional aim is to reveal how general (total) mental toughness and age predict each of the athletic mental toughness skills. The analysis of the results of the study revealed that players in the junior age group scored statistically significantly higher on the challenge, commitment, emotional control, life control, overall control, self-confidence in one's abilities, self-confidence in interpersonal interactions, overall self-confidence, total mental toughness, determination and visualization scales. Statistically significant correlations were found between mental toughness skills and the different age groups in all scales except positive cogni-tion and self-belief. Total mental toughness was a strong predictor of the athletic mental tough-ness skills, but age did not predict determination and self-beliefs skills.