Abstract: Objective：To explore the relationship between serum lactate dehydrogenase （ＬＤＨ） level and pre-eclampsia, adverse outcomes of pregnancy, and to confirm the predictive value of serum LDH level on pre-eclampsia. Methods：A retrospective study was performed in the present study which involved 2 236 patients with hypertensive disorders in Suzhou area of Jiangsu Province in China. The number of patients in gestational hypertension, mild and severe pre-eclampsia groups were 998, 305 and 933. Logistic regression was used to analyze the association between serum LDH and pre-eclampsia, the serum LDH and clinical records were investigated, and chi-square test was used to analyze the association between serum LDH and adverse outcomes of pregnancy. Results：①The level of LDH in group gestational hypertension was 228.0（１79.6-444.0） U/L. Significant difference （Ｐ＜０．０１） was revealed in serum LDH level between the gestational hypertension and pre-eclampsia groups, also between mild and severe pre-eclampsia groups. ②Patients were stratified according to quartiles of serum LDH. Compared the lowest quartiles （≤１７９．６ Ｕ/L）, the risk of pre-eclampsia increased significantly than the other three groups. Three models were used in logistic analysis, unadjusted model, adjusted model for tradition factors and adjusted model for selected factors by multiple regression. The odds ratｉｏ （ＯＲ） ａnd 95% confidence interval （９５％ＣＩ） for the three models were 18.92 （13.56-26.37）, 13.26 （９.42-18.6７） and 7.97 （５.37-11.8４） ｉn the highest quartiles （ＬDH＞444.0 U/L）, respectively. An obvious dose-response relationship was also showed in three models. ③For mild and severe pre-eclampsia patients, compared with the lowest quartiles （≤200 U/L）, the OR and 95%CI for the three models mentioned above were 11.5６ （６．７４－１９．８３）, 7.30 （４．２０－１２．７１） and 4.43 （2.47-7.94） for the highest quartiles （LDH＞547.0 U/L）, respectively. The pathogenesis risk increased with the LDH level elevation. ④The further ROC analysis showed that, the area under curve （ＡＵＣ） of serum LDH level, the ratio of LDH/albumin, and the ratio of LDH/bilirubin for the diagnosis prediction of pre-eclampsia or severe pre-eclampsia were lower than 0.8. The predictive value of the indexes above on pre-eclampsia or severe pre-eclampsia diagnosis was limited. ⑤When patients were stratified according to median of serum LDH, the elevation of serum LDH level was significantly （Ｐ＜０．０５） ｃorrelated to the adverse results of the pregnant women, fetuses and neonates in severe pre-eclampsia group. Conclusions：An obvious dose-response relationship was present between LDH level and pre-eclampsia, and LDH was an important reference biochemical marker in clinical practice, which reflected the severity of pre-eclampsia. In severe pre-eclampsia, the obvious elevation of serum LDH level might indicate the occurrence of maternal and infant adverse outcomes. Timely and effective measures might have very important significance to reduce the incidence of adverse outcomes of pregnancy, and protect the security and health of the maternal and children.