The primary aim of this study is to determine the value of using a combination of serum histidine-rich glycoprotein (HRG) level and uterine artery pulsatility index (PI) in pregnant women at 11-13+6 weeks' gestation to predict preeclampsia. The secondary aim is to determine the association between other pregnancy complications with the use of these combined tests. Transabdominal uterine artery PI and serum HRG level were measured at the time of first-trimester aneuploidy screening at 11-13+6 weeks' gestation in 327 pregnant women. The primary outcome was preeclampsia. The predictive values of this combination test were calculated. Eighteen cases developed preeclampsia (5.5%) and four of these preeclamptic cases were early-onset preeclampsia (1.2%). The sensitivity, specificity, positive predictive value, and negative predictive value of uterine artery PI combined with serum HRG level to predict preeclampsia were 11.1%, 96.8%, 16.7%, and 94.9%, respectively. For the prediction of early-onset preeclampsia, the sensitivity, specificity, positive predictive value, and negative predictive value were 25%, 97.1%, 10%, and 99%, respectively. An abnormal uterine artery PI and abnormal serum HRG level were associated with preterm delivery and intrauterine growth restriction. Our findings reveal that the combination of uterine artery PI and serum HRG level at 11-13+6 weeks of gestation is not an effective method for predicting preeclampsia at the time of first-trimester screening.