Purpose: This study was designed to verify preemptive effects of intravenous patient-controlled analgesia (IV-PCA) infusion on postoperative pain in women having a total abdominal hysterectomy. Method: The research design was a nonequivalent control group post test only design. The participants in this study were 50 women who were scheduled for a total abdominal hysterectomy at a University affiliated Hospital in Suwon, Korea. The subjects were divided into two groups. For the experimental group, IV-PCA infusion was started before the skin incision and for the control group. IV-PCA infusion was started after the skin was closed. Each group was evaluated in terms of pain score by the visual analogue scale (VAS) and the number of times they pushed the button for IV-PCA at postoperative hours 1, 2, 3, 6, 12, and 24. The data were collected from July 1 to December 10, 2001. Collected data was analyzed by SPSS/PC + program. Result: 1. There was no difference between the two groups, over six points for the number of times the control button for IV-PCA was used. Group differences and interaction effect were not significant. 2. There was no significant difference in pain scores between the two groups, over seven time points. A significant interaction effect was observed between groups and measurement Points in time. 3. There was a significant difference in the requirements for additional analgesia between the two groups, 32% of the control group received additional analgesia. Conclusion: Preemptive analgesics administration may have a better effect in relieving postoperative pain than the usual analgesic treatment which is started after surgery.