Intravenous patient-controlled analgesia(PCA) is gaining wide spread popularity in management of post-operative pain maintaining an effective blood concentrations of analgesics. We studied 48 patients, ASA class I or II, undergoing obstetric or gynecologic surgery under general anesthesia. We examined postoperative pain control level, patients satisfaction and side effects associated with the use of morphine and Baxter infusor. Each patient received 0.1 mg/kg as a loading dose and 0.0125 mg/kg/hr of morphine as maintenance dose. A unit was fitted with patient control module which had a flow rate of 0.5ml/hr and lockout interval was 15 minutes. Results were as follow. Pain scores were 1.88±0.81(first day), 1.31±0.71(second day). Visual analogue scales were 4.40±2.06(first day), 3.40±1.71(second day). 41 out of 48 patients in total were satisfied but nausea, dizziness or pruritus was noted. We recommend the use of PCA with morphine after surgery to improve post-operative pain because it provides adequate pain relief and a few side effects with high patients satisfaction.