This study was designed to examine the aerobic capacity and ventilatory response during an incremental exercise in elite high school cyclists. Twelve boys (17±1 yr, 175±5 cm, 70±9 kg) participated in anthropometric measurements, incremental exercise testing, and pulmonary function tests. During incremental exercise testing using a cycle ergometer, their maximal oxygen uptake (VO2max), maximal power output, ventilation, ventilatory equivalents for oxygen (VE/VO2) and carbon dioxide (VE/VCO2), respiratory rate, and tidal volume were measured. Time variables such as inspiratory time (Ti), expiratory time (Te), breathing time (Tb), and inspiratory duty cycle (Ti/Tb), as well as inspiratory flow rate (VT/Ti) were assessed. Pulmonary function of vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC, and peak expiratory flow were evaluated. Their VO2max, maximal heart rate, and Wmax were 57.5±3.9 ml·kg , and 452 W, respectively. VO2max was not related to any anthropometric parameters. Most ventilatory variables progressively increased with exercise intensity. As intensity increased, Ti, Tb, Tb decreased while Ti/Tb was maintained. Below an intensity of 250 W, height, weight, body mass index, and body surface were highly correlated with VT/Ti and Ti/Tb (p<0.05). Collectively, VO2max appeared to be lower than adult cyclists, suggesting a different pattern of ventilatory control as age advances. Morphological characteristics were not related to VO2max in the population. Time variables of ventilatory response seemed to be related only at an exercise intensity level of less than 250 W. VT/Ti may be related to exercise endurance capacity, but Ti/Tb was similar to adult cyclists.