Objective: Low-dose aspirin administration before 16 weeks of gestation can prevent preeclampsia more effectively. In order to determine if aspirin should be administered, this study aimed to investigate the predictive value of pregnancy-associated plasma protein A (PAPP-A) and aneuploidy markers for the onset period of preeclampsia (PE). Methods: 1053 singleton pregnant women were included in the study, and serum PAPPA-A and aneuploidy markers were analyzed between three group (normotensive, late-onset preeclampsia, and early-onset preeclampsia). The utility of these markers for predicting early-onset preeclampsia (EOPE) was compared using each marker and their combination. Results: Alpha-fetoprotein (AFP)/PAPP-A > 7.05 and human chorionic gonadotropin (hCG)/PAPP-A > 8.15 were associated with EOPE with a positive likelihood ratio (LR) (6.27, 95% confidence interval (CI) 4.7 6.9), and (5.23, 95% CI 3.5 5.8). The combination of markers could predict EOPE more accurately compared to the single markers. Conclusion: AFP/PAPP-A > 7.05 and hCG/PAPP-A > 8.15 had a predictive ability for EOPE, and these cut-off values can help determine the use of aspirin at an earlier gestational age.