The aim of this study was to evaluate the effectiveness of 12 weeks of balance training to improve the balance and vertical jump abilities of young basketball players. Twenty-three players from two teams in the Under Fifteen Basketball Excellence category participated in the study. Participants were divided into two training groups: balance training (BAL, n = 11) and isotonic training (ISO, n = 12). Both groups were tested for balance and vertical jumps at the beginning of the competitive season and at the end of 12 weeks of specific training programme. All of the tests were performed in sustained bipodalic and monopodalic (both right and left) positions. The results showed that players who participated in balance training for 12 weeks, compared to players who trained with isotonic machines, exhibited a significantly increase in balance (bipodalic 28.3 %; right 41.4 %; left 45.8 %; p < 0.01) and muscular power (bipodalic 8.1 %; right 13.5 %; left 12.5 %; p < 0.01) as measured through a vertical jump. In conclusion, balance training using unstable boards was an effective training method for improving balance and the vertical jump, which is a basketball-specific action that frequently occurs in this sport.