Background: Inconsistent sleep patterns may promote excess weight gain by increasing food cravings and loss-of-control (LOC)-eating; however, these relationships have not been elucidated in youth. Objective: We tested whether sleep duration and timing were associated with food cravings and LOC-eating. Method: For 14 days, youths wore actigraphy monitors to assess sleep and reported severity of food cravings and LOC-eating using ecological momentary assessment. Generalized linear mixed models tested the associations between weekly and nightly shifts in facets of sleep (i.e., duration, onset, midpoint, and waketime) and next-day food cravings and LOC-eating. Models were re-run adjusting for relevant covariates (e.g., age, sex, adiposity). Results: Among 48 youths (12.88 ± 2.69 years, 68.8% female, 33.3% with overweight/obesity), neither weekly nor nightly facets of sleep were significantly associated with food cravings (ps = 0.08–0.93). Youths with shorter weekly sleep duration (est. ß = −0.31, p = 0.004), earlier weekly midpoints (est. ß = −0.47, p = 0.010) and later weekly waketimes (est. ß = 0.49, p = 0.010) reported greater LOC-eating severity; findings persisted in adjusted models. Conclusions: In youth, weekly, but not nightly, shifts in multiple facets of sleep were associated with LOC-eating severity; associations were not significant for food cravings. Sleep should be assessed as a potentially modifiable target in paediatric LOC-eating and obesity prevention programs.