Two cases showed intermittent myoclonic movements in the lower extremities after receiving combined spinal-epidural anesthesia (CSE). Case 1: A 73-year-old female patient, underwent CSE, for a total knee replacement of right leg. Anesthesia was performed at L3/4 interspace with 2.0 ml of 0.5% tetracaine, mixed with normal saline and patient's own cerebrospinal fluid and epinephrine 1:200,000. Epidural catheter was inserted 3 cm-cephalad. Patient-controlled analgesia regimen was made with sufentanil 100 ug, 0.75% ropivacaine 30 ml, and naloxone 0.55 mg, with normal saline. The infusion regimen began at the end of the surgery, finished uneventfully after one and half hours. After 3 hours, the patient developed symmetric hip adductions of large amplitude and extensions of both legs for 2 to 3 seconds. Until valproate 800 mg was given, the movements repeated at 1 to 2 minute intervals for 3 hours. Case 2:The anesthesia and analgesia for 74-year-old female patient was done in similar fashion. Three hours after the end of operation, the patient showed myoclonic movements on right leg for about 30 seconds. The movements occurred at 2-3 minute intervals for the subsequent 2 hours and resolved spontaneously.