Cust, EE, Elsworthy, N, and Robertson, S. Analysis of training loads in elite under 18 Australian rule football players. J Strength Cond Res 32(9): 2521-2528, 2017-Differences in training loads (TLs) between under 18 (U18) Australian rules football (AF) state academy-selected and state academy-nonselected players were investigated. Players were categorized relating to their highest representative level: state academy-selected (n = 9) and TAC cup-level players (n = 38). Data were obtained from an online training-monitoring tool implemented to collect player training and match information across a 20-week period during the regular season. Parameters modeled included AF skills, strength, and other sport training sessions. Descriptive statistics (mean ± SD) and between-group comparisons (Cohen's d) were computed. A J48 decision tree modeled which TL variables could predict selection level. Pooled data showed 60% of weekly training duration consisted of AF training sessions. Similar AF TL were reported between state academy and TAC cup players (1,578 ± 1,264 arbitrary units (AU) vs. 1,368 ± 872 AU; d = 0.05). Although higher TLs were reported for state-selected players comparative with TAC cup in total training (d = 0.20), core stability (d = 0.36), flexibility (d = 0.44), on-feet conditioning (d = 0.26), and off-feet conditioning (d = 0.26). Decision tree analysis showed core stability duration and flexibility TL, the most influential parameters in classifying group selection (97.7% accuracy TAC cup level; 35.8% accuracy state academy level). Insights of U18 AF players' weekly training structures, loads, and characteristics of higher achieving players are provided. This study supports the application of training diaries and session rating of perceived exertion for TL monitoring in junior athletes.