The role of the natural hypoxic environment of the middle mountains in the growth of the erythrocyte link of the blood - erythrocytes, hemoglobin and the level of the average concentration of hemoglobin in erythrocytes, reflecting the level of iron sufficiency in the blood in children with autism spectrum disorders (ASD) is shown. The results of clinical blood tests showed that after 10-day courses of recovery in the mountains in the blood of children there are compensatory reactions associated with the restructuring of the body's blood supply - an increase in the number of red blood cells due to their intake from blood depots, which allows an increase in the level of hemoglobin and the volume of oxygen carried and improves blood circulation in the body of children.