Autism is a nervous system development disorder in a person who is more often involved by hereditary factors and can sometimes be detected since the baby starts 6 months. ADHD is a development in increasing motoric activity of children so that children's activities are unusual and tend to be excessive, whereas Down Syndrome is a genetic disorder that occurs during the growth of the fetus on chromosome 21 / trisomy 21 with varying changes. This research is aimed at looking at the factors that influence the nutritional status of children with Autism, ADHD & Down Sydrome. The study was a cross sectional design with a sample of 30 people. Retrieval of data on child weight, child's height, intake of energy, carbohydrate, protein, and fat consumption, parental income, parental education, children's physical activity and parental knowledge about children's diet. Held with in-depth observations and interviews. Data analysis was done by chi square test. The results of this study indicate no relationship between education, income, physical activity, protein, fat. There is a relationship between energy intake and knowledge of mothers with nutritional status.