Objective To characterize longitudinal trajectories of oral feeding performance of preterm infants during hospitalization in the NICU, to describe the influencing factors, and to provide reference for individualized management of oral feeding in preterm infants.Methods A convenience sample of 158 preterm infants were recruited and their oral feeding performance was assessed by using the Preterm Infant Oral Feeding Readiness Assessment Scale within 24 h of admission, at five milestones: first enteral fee-ding, complete enteral feeding, first oral feeding, half oral feeding, and full oral feeding, and also at discharge.The trajectories of oral feeding performance were analyzed using latent growth mixture modeling, and the influencing factors were identified through logistic regression.Results Three trajectory groups were identified:high-level and rising group （32.9%）, medium-level and rising group （47.5%） and low-level and falling then rising group（19.6%）.The logistic regression showed that, gestational age, birth weight, corrected gestational age at first oral feeding, severity of the disease and pre-feeding behavioral state were factors influencing trajectories （all P＜0.05）.Conclusion The oral feeding performance of preterm infants generally shows a gradual rising trend, with heterogeneous patterns of change.NICU healthcare professionals can perform targeted assessment and intervention based on the oral feeding performance trajectories in preterm infants to achieve precise care.