Extrauterine growth retardation is a critical indicator for assessing the development of preterm infants, yet its definition and diagnostic criteria remain inconsistent. This article analyzes the extrauterine growth retardation in preterm infants under various definitions and growth curves. Through a systematic review and comprehensive evaluation of existing studies, we elucidate the discrepancies among different definitions in diagnosing extrauterine growth retardation in preterm infants and predicting neurodevelopmental outcomes. Additionally, this paper provides an in-depth analysis of various methods and effects of neurodevelopmental nutritional interventions, offering novel insights and strategies to enhance the neurodevelopmental outcomes of preterm infants.