To explore the diagnostic value of the levels of miR-29b and ndothelial cell specific molecule-1 (ESM1) combined with thromboelastography results of pregnant women for their early-onset preeclampsia (PE). Methods: 93 pregnant women with early-onset PE treated in hospital from January 2022 to December 2023 were selected in study group retrospectively, and another 93 pregnant women with normal prenatal examinations were selected in control group. The levels of the serum miR-29b and ESM1 of the women in the two groups were analyzed, and the thromboelastography results of the women in the two groups were examined. The diagnostic efficacies of the levels of the serum miR-29b and ESM1 and the thromboelastography results of the women in the study group for their early-onset PE and the severity of their PE were explored. Results: The levels of serum miR-29b (1.45±0.54) and ESM1 (326.15±41.12 mmol/L) of the women in the study group were significantly higher than those (1.23±0.45 and 196.23±32.15 mmol/L) of the women in the control group, and the values of the reaction time, the coagulation time and the comprehensive coagulation index of the women in the study group were significantly lower than those of the women in the control group. The maximum amplitude of the women in the study group was significantly higher than that of the women in the control group (all P<0.05), and there was no significant difference in the horizontal angle of the women between the two groups (P>0.05). The area under the curve (AUC) of the miR-29b level, the ESM1 level, the reaction time value, the clotting time value, the maximum amplitude value and the comprehensive coagulation index value of the women for diagnosing their early-onset PE were 0.900, 0.921, 0.888, 0.821, 0.788, and 0.899, respectively, while the AUC value of the combined the miR29b and ESM1 levels, and the values of reaction time, clotting time, maximum amplitude and comprehensive coagulation index each index of the women for diagnosing their early-onset PE was 0.977. In the study group, there was no significant difference in the angle value between the women with mild PE and the women with severe PE (P>0.05). The serum miR-29b and ESM1 levels, and the maximum amplitude value of the women with severe PE were significantly higher than those of the women with mild PE. The values of the reaction time, coagulation time and comprehensive coagulation index of the women with severe PE were significantly lower than those the women with mild PE (all P<0.05). The AUC values of the miR-29b level, the ESM1 level, the reaction time value, the clotting time value, the maximum amplitude value and the comprehensive coagulation index value of the women for diagnosing their severe early-onset PE were 0.856, 0.884, 0.940, 0.667, 0.754, and 0.831, respectively. The AUC value of the combined the miR-29b and ESM1 levels, and the values of reaction time, clotting time, maximum amplitude and comprehensive coagulation index of the women for diagnosing their severe early-onset PE was 0.892. Conclusion: The levels of miR-29b and ESM1 combined with the thromboelastography results of the pregnant women for diagnosing their early-onset PE has higher value, and which of the pregnant women for their severity of early-onset PE has also higher diagnostic efficiency.