Objective：To explore the diagnostic value of RIFLE criteria and acute kidney injury network（AKIN） criteria in diagnosing child acute kidney injury（AKI） in order to help early diagnosis and treatment of children with AKI. Methods：Totally 223 hospital－ized children with AKI in our hospital were retrospectively analyzed，including clinical features，laboratory indicators，therapeutics，outcome，etc. Diagnostic value of the RIFLE criteria and AKIN criteria for children AKI was explored. Results：AKIN criteria has no obvious advantage in the diagnosis of AKI children compared with RIFLE criteria（ χ2=1.000，P=0.962）. In terms of staging diagnosis，there’s no significant statistical difference（ χ2=2.303，P=0.316） between stage 1，stage 2，stage 3 in AKIN criteria and the corresponding risk，damage，failure phase in RIFLE criteria. Regardless of AKIN criteria or RIFLE criteria，the distribution of prognosis（RI－FLE criteria： χ2=11.526，P=0.003；AKIN criteria： χ2=13.559，P=0.001），mechanical ventilation rate（RIFLE criteria： χ2=12.119，P=0.002；AKIN criteria： χ2=6.854，P=0.032），blood purification rate（RIFLE criteria： χ2=43.569，P=0.000；AKIN criteria： χ2=88.766，P=0.000） and incidence of multiple organ dysfunction（RIFLE criteria： χ2=11.896，P=0.003；AKIN criteria： χ2=11.783，P=0.003） in different AKI stages were significantly statistically different. In-hospital mortality increased with the increase of the severity of AKI（stage of AKI）. In-hospital mortality of children with AKI in failure phase（stage 3） was significantly higher than that in risk phase（stage 1） and injury phase（stage 2）. Nevertheless，there’s no statistical difference in cure rate（RIFLE criteria： χ2=1.896，P=0.388；AKIN cri－teria： χ2=3.646，P=0.162） and average hospitalization days（RIFLE criteria：F=1.540，P=0.217；AKIN criteria：F=0.037，P=0.963） among different AKI stages. Conclusion：AKIN criteria have no obvious advantage in the diagnosis，staging diagnosis and eval－uation of short-term prognosis of AKI children compared with RIFLE criteria. Regardless of AKIN criteria or RIFLE criteria，the increase of kidney injury severity in AKI children is closely related with poor short-term prognosis. As the severity of AKI（the stage of AKI） increases，mechanical ventilation rate，blood purification rate，incidence of multiple organ dysfunction increase. In-hospital mortality of children with AKI in failure phase（stage 3） is significantly higher than that in risk phase（stage 1） and injury phase（stage 2）. However，there’s no statistical difference in cure rate and average hospitalization days among different AKI stages.