Many medication errors can occur when ordering and dispensing medicine in hospitals. The clinical decision support system (CDSS) is widely used in an effort to reduce medication errors. This study focused on the evaluation of user satisfaction with the CDSS for medication at a university hospital. Specifically, this study aimed to identify the factors influencing user satisfaction and to examine user requirements in order to further improve user satisfaction and drug safety.The study was based on survey data from 218 users (103 doctors, 103 nurses, and 15 pharmacists) at a university hospital that uses the CDSS. In order to identify the factors influencing user satisfaction with the CDSS, a multiple linear regression was performed. In order to compare the satisfaction level among the professional groups, an analysis of variance (ANOVA) was performed.The reliability of information, decision supporting capability, and departmental support were significant factors in influencing user satisfaction. In addition, nurses were the most satisfied group, followed by pharmacists and doctors according to the ANOVA. Areas for further improvement in enhancing drug safety were real time information searching and decision supporting capabilities to prevent adverse drug events (ADE) in a timely manner.We found that the CDSS users were generally satisfied with the system and that it complements the nationwide drug utilization review (DUR) system in reducing ADE. Further CDSS evaluation in other hospitals is needed to improve user satisfaction and drug safety.