Abstract： Background: Preeclampsia (PE) is a serious idiopathic disease posing a threat to both mothers and fetuses' lives during pregnancy, whose main diagnostic criteria include hypertension with proteinuria.However, American College of Obstetricians and Gynecologists (ACOG) updated the diagnostic criteria for PE and reduced the diagnostic value of proteinuria for patients with PE.Qualitative analysis of the diagnostic value of 24-h proteinuria for patients with PE in China was conducted to evaluate the diagnostic criteria value in the latest ACOG guideline.Methods: Complete clinical data of 65 patients with hypertensive disorder in pregnancy (HDP) were collected.All patients were delivered to and hospitalized in Renji Hospital.Adverse outcome was defined in case of the emergence of any serious complication for a mother or the fetus.A retrospective study was conducted according to ACOG guideline, to analyze the relationship between each diagnostic criteria of ACOG guideline and maternal and perinatal outcomes.Spearman correlation test was used to detect the association between each diagnostic criterion, its corresponding value, and the adverse pregnancy outcome.Logistic regression was performed to verify the result of Spearman correlation test.Results: Of 65 HDP patients, the percentage of adverse pregnancy outcome was 63.1％.Adverse pregnancy outcomes constitute diversification.There were 55 cases with 24-h proteinuria value ≥0.3 g, of which the adverse outcome rate was 74.5％.While adverse pregnancy outcomes did not appear in the rest 10 HDP patients with proteinuria ＜0.3 g/24 h.The statistic difference was significant (P =0.000).However, no significant difference was found in other criteria groups (impaired liver function: P =0.417;renal insufficiency: P =0.194;thrombocytopenia: P =0.079;and cerebral or visual symptoms: P =0.296).The correlation coefficient between 24-h proteinuria ≥0.3 g and adverse pregnancy outcomes was 0.557 (P ＜ 0.005).Impaired liver function (P =0.180), renal insufficiency (P =0.077) and cerebral or visual symptoms (P =0.118) were not related to adverse outcomes.The 24-h proteinuria value (HDP: r =0.685;PE: r =0.521),liver enzyme value (HDP: r =0.519;PE: r =0.501), and creatinine value (HDP: r =0.511;PE: r =0.398) were associated with adverse pregnancy outcomes both in PE and HDP, and the corresponding logistic regression equation can be produced.Conclusions: The 24-h proteinuria value is still an important diagnostic criterion for PE, and deletion of 24-h proteinuria value from diagnostic criteria for severe PE was not recommended.The diagnostic criteria in ACOG guideline need to be verified in Chinese women.