Early childhood is a critical stage of growth and development, and the nutritional status of this period not only affects physical growth and development, but also lays a solid foundation for lifelong health. However, due to the rapid growth and metabolic characteristics of infants and young children, coupled with the immaturity of multiple physiological systems and the high incidence of infectious diseases, this population faces nutritional risks. This review synthesizes relevant domestic and international studies to elucidate the current landscape of infant nutrition risk, as well as the associated influencing factors such as life environment, age, disease, and high-risk conditions. The paper also shows the design, application, scope, and limitations of existing infant nutrition risk screening tools, along with the clinical significance of nutritional risk screening in hospitalized children, outpatient clinics, and specialized settings. The primary objective of this paper is to raise awareness among pediatric clinicians regarding infant nutrition issues and to promote proactive nutritional risk screening, thereby facilitating early identification of nutritional risks and ultimately achieving standardized and scientific nutrition management.