Malnutrition in early childhood is a significant public health issue affecting cognitive development worldwide. Lesotho, an African country with high rates of malnutrition and underdevelopment, offers unique insights into this phenomenon. Participants were recruited from urban and rural areas, stratified by socio-economic status (SES). A standardised assessment tool was used to measure cognition, including language skills, memory, and problem-solving abilities. Nutritional status was assessed through anthropometric measurements and dietary surveys. Children with moderate malnutrition showed a significant decline in verbal fluency scores compared to those without malnutrition, indicating impaired cognitive flexibility. The findings suggest that early intervention programmes targeting nutritional support are essential for mitigating the negative impacts of malnutrition on cognitive development in Lesotho. Public health initiatives should prioritise community-based nutrition education and supplementation programmes to improve children's cognitive outcomes.