Objective:To investigate the relationship between exercise related syncope and iron deficiency anemia in children, and analyze the effect of nutrition supply on exercise related syncope.Methods:Three hundred and six children with iron deficiency anemia in Quanzhou Medical College People′s Hospital Affiliated from June 2018 to June 2020 were enrolled, and they were divided into two groups: observation group (105 Children with exercise related syncope) and control group (201 Children without exercise related syncope). General data, red blood cell parameters, iron metabolism index and blood trace element level were compared between two groups. The daily food composition, the intake of three major nutrients, trace elements and Vitamins were analyzed.Results:The body mass index and waist-to-hip ratio in the observation group were lower than those in the control group, the blood oxygen saturation was lower than that in the control group, the proportion of males, severe anemia, picky eaters and more intake of snack were higher than those in the control group, the differences were statistically significant ( P<0.05). The levels of hemoglobin, mean corpuscular hemoglobin concentration and mean corpuscular volume in the observation group were lower than those in control group: (70.12 ± 9.68) g/L vs. (83.64 ± 10.12) g/L, (20.12 ± 3.64) pg vs. (26.97 ± 3.52) pg, (63.46 ± 8.46) fl vs. (71.34 ± 8.12) fl; and the red blood cell distribution width was higher than that in control group: 0.258 ± 0.058 vs. 0.201 ± 0.064, the differences were statistically significant ( P<0.05). The levels of serum ferritin content and total iron binding capacity in observation group were higher than those in the control group: (136.58 ± 28.71) ng/L vs. (113.21 ± 24.45) ng/L, (69.64 ± 7.23) μmol/L vs. (56.48 ± 8.65) μmol/L, the levels of serum ferritin and transferin saturation were lower than those in the control group: (15.32 ± 4.15) μmol/L vs. (17.69 ± 4.21) μmol/L, 0.198 ± 0.056 vs. 0.265 ± 0.062, the differences were statistically significant ( P<0.05). The levels of blood calcium and zinc in the observation group were lower than those in the control group: (5.44 ± 0.28) mmol/L vs. (5.63 ± 0.34) mmol/L, (63.23 ± 2.73) μmol/L vs. (68.42 ± 2.65) μmol/L, the differences were statistically significant ( P<0.05). The daily intake of cereals, meats, vegetables and fruits, beans, eggs and milk in the observation group were lower than those in the control group, the daily intake of sugar and protein in the observation group were lower than those in the control group, the daily intake of iron, Vitamin C and Vitamin A in the observation group were lower than those in the control group, the differences were statistically significant ( P<0.05). Conclusions:Iron deficiency anemia in Children may be one of the risk factors of exercise related syncope. Health education should be strengthened for children and their parents. Moreover, change of unhealthy diet behavior and adjustment of dietary structure can reduce the incidence of exercise related syncope.