Often in extremely preterm newborns in the early postnatal daysproblems in fluid and electrolyte balance occur Due to excessive insensible water loss and renal immaturity. The dietary care of newborn newborns is challenged by the demands of growth and organ development. The stress of a serious disease makes it much more difficult to get enough nourishment. Newborns andespecially premature newborns must be assessed thoroughly for fluid and electrolytes balance. Calculating the fluid and electrolyte demand for sustaining metabolic activities, replacing losses (evaporative, third space, external), and considering pre-existing fluid imbalance are all part of effective fluid and electrolyte management. When a neonate's size or condition prevents them from receiving enteral nutrition, parenteral nutrition can help them grow and thrive. Although eating through the gastrointestinal tract is the recommended method of nutritional management, some situations necessitate the use of PN as an adjuvant or sole treatment. In this article we discuss fluid electrolytes and Nutritional management using parenteral nutrition.