Purpose: The goal of this study was to examine the effects of a preoperative education program in patients receiving Patient-Controlled Analgesia (PCA) in a Korean military hospital. Methods: This study is nonequivalent control group, non-synchronized design quasi-experimental research. Patients were assigned to either the experimental (n=39) or the control group (n=34). The experimental group was provided with both an intensive preoperative education and a standard postoperative education about PCA while the control group received a standard postoperative education only. Knowledge of pain, knowledge of PCA, attitude to pain and analgesic, and postoperative pain scores at 8, 24, 48 hours were measured through questionnaires. The collected data was analyzed with χ2–test, t-test, ANCOVA and Generalized Estimating Equations. Results: Knowledge of pain significantly increased in the experimental group(F=4.47, p=.038) more than it did in the control group. Although knowledge of PCA increased and attitude of pain and analgesic improved in both groups. the gap between the two groups was not statistically significant. Postoperative pain at 8, 24, 48 hours improved in both groups, but the degree was not statistically significant. Conclusion: Intensive preoperative PCA education was effective in increasing knowledge of pain, but did not significantly improve knowledge of PCA, attitude of pain and analgesic, postoperative 8, 24, 48 hours pain score. A further study controlling various factors(e.g. type of anesthesia) and comprehensive pain management program may be needed to improve the attitude of pain and analgesic.