Objective To investigate the correlation between mean platelet volume（MPV）

platelet distribution width（PDW）

and platelet larger cell ratio（P-LCR） and platelet count in children with idiopathic thrombocytopenic purpura（ITP）. Methods Sixty-five children with ITP treated in a hospital in Henan Province from May 2017 to May 2020 were selected for this study. The children were divided into 2 groups according to platelet counts

i.e.

mild-medium and severe groups. The MPV

PDW

and P-LCR of the children in the 2 groups were compared; the relationship between MPV

PDW

and P-LCR and platelet count in children with ITP was analyzed by bivariate Pearson linear correlation; and the relationship between MPV

PDW

and P-LCR and the severity of the disease in children with ITP was analyzed by logistic regression. Results Among the 65 children

37 had mild to moderate ITP

with platelet counts of（35.64±8.73）×10~9/L and 28 had severe ITP

with platelet counts of（13.46±3.18）×10~9/L. The differences were statistically significant（P<0.05） when comparing the platelet count levels of the 2 groups of children. The MPV

PDW

and P-LCR levels of children in the severe group were higher than those in the mild to moderate group

and the differences were statistically significant（P<0.05）. Bivariate Pearson linear correlation analysis revealed that MPV

PDW

and P-LCR were negatively correlated with platelet count in children with ITP（P<0.05）. The results of logistic regression analysis showed that high expression of MPV

PDW

and P-LCR were all independent influencing factors on the severity of ITP disease（P<0.05）. Conclusion The levels of MPV

PDW and P-LCR can be used to predict the severity of the disease in children with ITP

and clinical interventions can be performed early according to the changes of these parameters to control the further development of the disease.