Sleep problems affect 20%-30% of toddlers and preschoolers. Few longitudinal studies focused on the impact of infant feeding practices on sleep. We aimed to study the associations between feeding practices up to 8 months and trajectories of sleep quantity or quality from 2 to 5-6 years. Analyses included 1,028 children from the EDEN mother-child cohort. Data were collected by self-administered questionnaires. Associations between feeding practices (breastfeeding, complementary feeding, use of thickened infant formula, night feeding) and sleep trajectories (sleep-onset difficulties, night waking, nighttime in bed) were analysed by multiple logistic regressions. Predominant breastfeeding for more than 4 months was associated with lower risk for belonging to the persistent sleep-onset difficulties trajectory. Night feeding at 4 months or at 2 years old was associated with higher risk for belonging to the persistent sleep-onset difficulties trajectory, and night feeding at 8 months was associated with higher risk for night waking and higher risk for short nighttime in bed. Early introduction (< 4 months) to complementary foods (excluding baby cereals) was related to lower risk for short nighttime in bed. Use of baby cereals or thickened infant formula was related neither to sleep quality nor to sleep quantity. In conclusion, infant feeding practices are associated with sleep trajectories in preschoolers, with notably a potential protective role of breastfeeding. Further researches are needed to clarify the mechanisms of these relationships. © 2019 European Sleep Research Society.