Purpose: This study aimed to analyze the development of pacing behavior of athletes during adolescence using a longitudinal design. Methods: Lap times of male short-track speed skaters (140 skaters, 573 race performances) over two or more 1500-m races during Junior World Championships between 2010 and 2018 were analyzed. Races were divided into four sections (laps 1-3, 4-7, 8-11, and 12-14). Using MLwiN (P < 0.05), multilevel prediction models in which repeated measures (level 1) were nested within individual athletes (level 2) were used to analyze the effect of age (15-20 yr), race type (fast, slow), and stage of competition (final, nonfinal) on absolute section times and relative section times (percentage of total time spent in a section). Results: Between the ages of 15 and 20 yr, total race time decreased (-6.99 s) and skaters reached lower absolute section time in laps 8-11 (-2.33 s) and 12-14 (-3.28 s). The relative section times of laps 1-3 (1.42%) and 4-7 (0.66%) increased and of laps 8-11 (-0.53%) and 12-14 (-1.54%) decreased with age. Fast races were more evenly paced compared with slow races, with slow races having a predominantly slow first half and fast finish. Athletes in finals were faster (2.29 s), specifically in laps 4-7 (0.85 s) and laps 8-11 (0.84 s). Conclusion: Throughout adolescence, short-track speed skaters develop more conservative pacing behavior, reserving energy during the start of the race in order to achieve a higher velocity in the final section of the race and a decrease in total race time. Coaches should take into consideration that the pacing behavior of young athletes develops during adolescence, prepare athletes for the differences in velocity distribution between race types, and inform them on how to best distribute their efforts over the different stages of competition.