Objective To evaluate the optimal Kryptor threshold for sFlt-1/PlGF on PE among the hypertensive pregnant women. Design A single centre prospective study. Setting Guangzhou Women and Children’s Medical Care Center. Population or Sample 565 singleton pregnant women with hypertension from January 2018 to June 2021. Methods PlGF/sFlt-1 and perinatal data were collected and logistic regression was used to explore the cutoffs of sFlt-1/PlGF for PE from different hypertension types in HDP. Main outcome measures PlGF/sFlt-1 cutoff of PE and chrHBP with PE in HDP . Results: The sFlt-1 /PlGF ratio in PE and chrHBP with PE were significantly higher than GH & chrHBP, in which early-onset were higher. For gestatioanl hypertension, sFlt-1 /PlGF ratio> 36.44 could rule in PE occurence(AUC=76.17% - 78.39%) in 1-4week with PPV 0.91-0.94 & NPV 0.67 before 34 weeks, while sFlt-1 /PlGF ratio< 51.52 could rule out PE occurrence (AUC=75.29% - 78.39%) in 1-4 weeks with NPV 0.91-0.96 & PPV 0.62-0.73 after 34 weeks. For chronic hypertension, sFlt-1 /PlGF ratio> 47.78 could rule in PE occurrence (AUC=82.5% - 86.36%) in 1-4 weeks with PPV 0.9-0.96 & NPV 1.0 before 34 weeks, while sFlt-1 /PlGF ratio< 28.61 could rule out PE occurence(AUC=72.41% - 73.03%) in 1-4 weeks with NPV 0.88 & PPV 0.43-0.79 after 34 weeks. Conclusion: Lower sFlt-1/PlGF had high positive potential to identify the patients to develop early onset PE from gestational and chronic hypertension, which could complement the strategy to hypertensive disorders in pregnany. Funinding Guangzhou science and technology Program Project (202102010163) .