A cross section study was conducted to assess the nutritional status and cognitive development of children under 6 years old in Tran Hung Dao ward - Phu Ly city, Ha Nam province. 350 children - mother pairs were recruited for this study. The results showed that the malnutrition prevalence was low but the overweight was alarming. The prevalence rate of underweight malnutrition was 4.3 percent, the stunting was 7.1 percent and the wasting was 7.1 percent. Malnutrition was found in the early months of children with the upward trend through their age especially in the underweight malnutrition. The overweight prevalence rate was 12.9 percent. The cognitive development of these children was generally quite good. Almost cognitive development was in progress and normal areas, the proportion of personal interaction was lower (40.6 percent). There was no correlation observed between the level of cognitive development al)d the nutritional status of children.