The sequential combined spinal epidural(CSE) block combines the reliability of spinal block with the flexibility of epidural block. The present study was designed to compare CSE block with spinal block for cesarean section. The quality of surgical analgesia and the effect on maternal blood pressure, complications, and neonatal status were evaluated. Thirty healthy parturients were randomly divided into a spinal(n=15) and a sequential CSE(n=15) group. In the spinal group, 0.5% hyperbaric bupivacaine, 2.5 ml, was injected into subarachnoid space through a 26-gauge Quincke needle. In the sequential CSE group, 1,5 ml of 0.5% hyperberic bupivacaine was injected into the subarachnoid space through a long 26-gauge Quincke needle, which was introduced through an 18-gauge Tuohy needle. An epidural catheter was then inserted. If the block in the sequential CSE group did not reach the T(4) level in 15 min., it was extended by fractionated doses of 0.5% bupivacaine administered through the epidural catheter. Ephedrine, 5~10 mg intravenously(IV), was given to treat hypotension(20% decrease from baseline value). The time intervals from induction of block to start of surgery was shorter in the spinal group(P<0.05). Cephalad spread of block(pinprick) 15 min. after induction was T3(T2 T6)(median[range]) in spinal group and T9(T6-T12.)in the sequential CSE group(P<0.05). All patients in sequential CSE group needed epidural bupivacaine, 51.3+/-3.5 mg(mean+/-SEM). The surgical analgesia and muscle relaxation was excellent or good in 86% in both groups. After delivery, patients in both groups needed a similar amount of supplementary fentanyl and midazolam IV. Hypotension occurred in 80%(spinal block) and 13.3%(CSE block) but developed earlier in spinal group(P<0.05). Apgar score did not indicate any differences between the two regional anesthesia techniques. The postdural puncture headache(PDPH) was the most common complication of both group(40% and 33.3%) and most of them were improved spontaneously without specific medications. Both spinal and sequential CSE block provide good surgical analgesia for cesarean section. Maternal hypotension is a risk with both technique, but it occurs more frequently and earlier with spinal block. There is no difference in Apgar score, provided that maternal blood pressure is cautiously monitored and hypotension promptly treated. PDPH was the most common complication of both group, but can be diminished with paralleled needle insertion to the dural fiber and the use of smaller sized round-tip needle.