Absract ASD research continues to receive considerable attention as the options for successful management are limited. The understanding of the Autism Spectrum Disorder (ASD) etiology has now progressed to encompass genetic, epigenetics, neurological, hormonal, and environmental factors that affect outcomes for patients with ASD. Glycosaminoglycans (GAGs) are a family of linear, sulfated polysaccharides that are associated with central nervous system (CNS) development, maintenance, and disorders. Proteoglycans (PG) regulate diverse functions in the central nervous system. Heparan sulfate (HS) and chondroitin sulfate (CS)are two major glycosaminoglycans (GAG) present int he PGs of the CNS. Most neurotransmitter problems appear to be genetic in nature and involve abnormal absorption, metabolism or storage of key nutrients. As neuroscience advances, biochemical treatments to correct brain chemistry become better defined. Nutrient therapy can be very potent and does not involve side effects, since no molecules foreign to the body are needed. We found statistically significant difference in total GAG excretion between 18 control subjects and 32 patients with ASD . The tGAG concentration was significantly higher in ASD patients (26/32, 81.2%) than in normal children. The main fractions: heparan sulfate and chondroitin-4/6-sulfate). The 14 consecutive subjects who were placed on the elimination diet (casein-free, special carbohydrates, multivitamin/mineral supplement), occupational therapy and adaptive sports), showed significantly different (low) urinary tGAG excretion.