Objective To investigate the low hemoglobin density (low haemoglobin density,LHD) and red blood cell volume distribution width (red blood cell volume distribution width,RDW) in iron deficiency anemia (iron-deficiency anemia,IDA)in children with the value of diagnosis and treatment.Methods From February 2016 to May 2017,in the Second People's Hospital of Longgang District in Shenzhen City,86 cases of children with iron deficiency anemia for IDA group,and 120 cases of healthy children (as the control group) at the same time were confirmed.Blood routine of children with IDA were detected before and after treatment hemoglobin concentration and the results were analyzed statistically.Results 120 cases of healthy children in the peripheral blood LHD value was 2.74 ％ ± 0.90 ％ and the boy was 3.07 ％ ± 0.81％,higher than that of 2.26 ％ ± 0.69 ％ of the girls.Between them,there was statistically significant difference (t=3.815,P＜0.05).The value of RDW was 12.37 ％ ± 2.84 ％,12.09 ％ ± 2.80 ％ for the boys and 12.56 ％ ± 2.87 ％ for the girls,there was no statistically significant difference between the them (t=0.517,P＞0.517).Before treatment,86 cases of children with IDA LHD and RDW values in peripheral blood were 30.67 ％ ± 20.12 ％ and 16.62 ％ ± 3.27 ％,significantly higher than the control group,the difference was statistically significant between (t=4.025 ～ 4.025,P＜0.05 ～ 0.01),and there was no statistically significant difference between male and female children (t =0.761 ～ 0.917,P＞ 0.05).After treatment L HD and RDW values were 10.65 ％ ± 8.92 ％ and 14.02 ％ ± 2.93 ％,significantlylower than before the treatment,between them was statistically significant difference (t=2.912～9.675,P＜0.05).Conclusion Children with iron deficiency anemia treatment before the LHD and RDW values significantly elevated in the blood,significantly decreased after treatment,the LHD and RDW values for diagnosis and treatment of children with iron deficiency anemia dynamic monitoring has certain application value,worthy of popularization and application.