Effects of epidural continuous infusion were compared with those of intermittent injection method in 50 primigravid parturients in active labor. After the intial bolus epidural injection of 0.25% bupivacaine 7-10ml, the parturients were divided randomly assigned to either continuous epidural infusion(INF) group or no infusion control(CONT) group. INF group received continuous epidural infusion of 0.125% bupivacaine 10ml h(-1). The parturients in both groups received intermittent top-ups of 0.25% bupivacaine 5ml with pain above 4 on visual analog scale. Epidural administration of bupivacaine was discontinued at the beginning of second stage of labor. No difference was noted between the two groups compared with respect to pain score during first stage of labor and to duration of epidural analgesia and second stage of labor. The mean pain score during second stage was lower and the general patient satisfaction was greater in INF group. The time interval between top-ups was longer in INF group than in CONT group. The total dose of bupivacaine administered during epidural analgesia was more in INF group than in CONT group. However the difference of hourly dose between two groups when the duration of epidural anagesia exeed four hours was not significant. No parturients in either group experienced severe hypotension, high level of sensory blockade or heavy motor blockade. We conclude that continuous epidural infusion seems capable of keeping parturient's hemodynamics stable during labor, and offers greater satisfaction and safety to the parturients.