The purpose of this study was to analyse the characteristics of physique and physical fitness and to investigate the effects of athlete\'s physique and physical fitness to athletic performance of sprinters, middle and long distance runners. jumpers and throwers group with 160 track and field athletes of Boy\'s middle in Pusan metropolitan city. In this study 7 tactors in physique, 9 factors in physical fitness and 17 factors in athletic performance were measured and analyzed. The results of the study were as follows: 1. The characteristics of the physique factors In Boy\'s middle school throwers group was the biggest and middle and long distance runners group was the smallest in each factors. 2. The characteristics of the physical factors In Boy\'s middle school throwers group was higher in muscular strength agility and flexibility, sprinters group in muscular strength and power and middle and long distance runners group in balabce than other groups. 3. The relationship between physique factors and athletic performances In Boy\'s middle school sprinters group was significantly related to standing height, middle and long distance runners group to lower limb length, jumpers group to standkin height, upper limb length lower limb length and chest girth and throwers group to all factors. 4. The relationship between physical fitness factors and athletic performances In boy\'s middle school sprinters group was significantly related to power, middle and long distance runners group to powern muscular endurance and cardiorespiratory endurance jumper group to muscular strength, power, balance and muscular endurance and throwers group to muscular strength agility power muscular endurance and cardiorespiratory endurance.