The aim of the paper is to present different techniques for measuring body composition in neonates and the importance of its assessment for monitoring adequate growth and predicting neonatal- and later-life morbidity. Follow up of neonatal growth is even more important in specific groups of newborns, for example preterm infants, newborns with congenital heart disease and newborns with kidney anomalies. There are several models that divide body into compartments containing specific components. None of the measuring techniques embraces all of the body components, but with accurate and quality assessment of body compartments growth can be followed quite successfully. We believe that measuring body composition in vulnerable and sick neonates can contribute to better enteral support and management resulting in optimal growth and short- and long-term outcomes in these children. Conclusion – Optimal growth in infancy has significant impact on neurodevelopment and adult life disease programming. There are several different techniques for measuring body composition and some of them can be easily introduced in everyday clinical practice.