Basketball is a team sport that consists of many technical and tactical elements. The performance of these elements requires a certain level of motor skills and knowledge. The player's mobility, i.e. the range of motion in individual joint systems, is essential for the smooth performance of basketball elements, and a low level of flexibility is also associated with numerous injuries of the locomotor system. The aim of the work is to determine the differences in range of motion between young basketball players of the national selection. The research was conducted on young basketball players of the national selection who were divided into an older cadet category (U16), which included 16 subjects with an average age of 15.98±0.28 years, height 194.45±7.59 centimeters, body weight 84.77 ±10.72 kilograms and 16.09±3.01% of adipose tissue and the younger cadet category (U15) which also included 16 subjects with an average age of 15.10±0.30 years, height 188.79±7.44 centimeters, body weight 72.42±9.93 kilograms and 14.81±2.45% of adipose tissue. Using the Gyko system, 6 variables were observed to assess the extent of movement: the maximum angle during the performance of the forehand with the right hand (Fore_H_R); maximum angle during the execution of the left hand forehand (Fore_H_L); the maximum angle during the execution of the right handed handoff (Ha_H_R); the maximum angle during the execution of the left hande handoff (Ha_H_L); the maximum angle during the performance of the forefoot with the right leg (Fore_L__R); the maximum angle during the performance of the forefoot with the left leg (Fore_L_L). The results showed that there is a statistically significant difference in the variables forehand_L (p=0.04), forefoot_L (p=0.02) and forefoot_D (p=0.04), while no statistically significant difference was found in the other variables.