Abstract: Objective：To compare the effects of crystalloid and colloid coload on placental circulation for puerperae underwent spinalepidural anesthesia and fetus. Methods：Totally 100 cases scheduled for planned cesarean delivery under spinal anesthesia were recruited for this study. American Society of Anesthesiologists (ASA) score was ⅠⅡ. Parturients were randomly selected into H group and R group, with 50 cases in each group. H group was received 6% hydroxyethyl starch 130/0.4 sodium chloride injection, while the R group was applied with Lactated Ringer solution. Two groups were received speedy injection of HES or Lactated Ringer solution before spinalepidural anesthesia, the speed with 0.4 mL/（kg·min） until delivery. The dilatation stopped immediately after delivery, and puerperal received routine infusion according to haemodynamics. Before anesthesia, 5 min after anesthesia, the systolic/diastolic ratios （S/D）, pulsatility index （PI）and resistance index （RI）were detected by using color Doppler ultrasound. After delivery, the umbilical artery blood and umbilical veins blood were analyzed, and the Apgar scores were compared. Phenylephrine 0.1 mg was applied for hypotension during surgery. Results：After spinalepidural anesthesia, the umbilical artery PI and S/D in two groups were reduced. There was no statistical significance of RI between before anesthesia and after anesthesia or between two groups. The incidence of hypotension during surgery in H group was lower than that in R group (P=0.03). The phenylephrine requirements in R group was higher than that in H group (P=0.001). There was no statistical significance of blood gas analysis and Apgar score in two groups. Conclusions：The spinalepidural anesthesia can lower the resistance of umbilical artery blood. Comparing to Lactated Ringer′s solution, colloid coload significantly increased placental perfusion, and decrease the incidence rate of hypotension during surgery.