Child nutrition is a cornerstone for growth, development, and health, addressing the challenges posed by the triple burden of malnutrition: undernutrition, hidden hunger, and overnutrition. This chapter explores the nutritional needs of children across developmental stages, from newborns to school-aged children, emphasizing the roles of macronutrients (proteins, fats, and carbohydrates), micronutrients (vitamins and minerals), and water in fostering physical and mental growth. The chapter highlights the significance of exclusive breastfeeding in infancy, balanced diets in early childhood, and the importance of tailored calorie intake during preschool and school years. Nutritional deficiencies, including protein-energy malnutrition, vitamin deficiencies, and mineral insufficiencies, are discussed alongside their clinical manifestations, such as kwashiorkor, marasmus, and rickets. Additionally, overnutrition’s impact on childhood obesity, diabetes, and other health conditions is examined. Practical dietary recommendations, including appropriate food sources and supplements, are provided to ensure optimal growth and development.