Preeclampsia (PE) is a severe pregnancy complication characterized by significant alterations in coagulation function. This study aims to analyze the correlation between coagulation function, platelet parameters, and pregnancy outcomes in PE patients. Clinical data, along with blood and urine samples, were collected from 168 PE patients and 128 healthy pregnant women. General demographic and laboratory testing data were recorded, and maternal and fetal outcomes were followed up. Data were analyzed using Kaplan-Meier and logistic regression analyses. In mild PE patients, thrombin time (p = .000), platelet distribution width (PDW) (p = .000), and clot formation time (p = .000) were increased, while prothrombin time (p = .000) and fibrinogen (p = .045) were reduced. With increasing PE severity, prothrombin time (p = .000), platelet count (PLT) (p = .000), mean platelet volume (MPV) (p = .000), plateletcrit (p = .000), maximum amplitude (MA) (p = .000), and coagulation index (p = .001) decreased, whereas activated partial thromboplastin time (APTT) (p = .000), thrombin time (p = .002), D-dimer (p = .026), and PDW (p = .000) increased. Lower prothrombin time (p = .048), PLT (p = .004), and coagulation index (p = .026) or higher APTT (p = .032), thrombin time (p = .044), D-dimer (p = .023), and PDW (p = .016) were associated with a higher risk of poor pregnancy outcomes. Thrombin time was identified as an independent risk factor (p = .025, OR = 2.918, 95% CI: 1.145-7.436), whereas gestational age was an independent protective factor (p = .000, OR = 0.244, 95% CI: 0.151-0.395). This study demonstrates that specific coagulation and platelet parameters are significantly associated with PE severity and adverse pregnancy outcomes. These findings highlight the importance of monitoring coagulation function in PE patients to improve clinical management and outcomes.