Drug Utilization Review (DUR) is known to play an important role to improve appropriateness of drug prescriptions. This retrospective, observational study was conducted to compare prescription patterns after installation of Computerized DUR Program (Drug Information Framework-$Korea^{TM}$) (Jan-Mar 2008; After) to before DUR program (Jan-Mar 2007: Before). 8 physicians affiliated in the S University Hospital were enrolled in the study and their 3 months' prescription data were analysed for drug prescription trends and DUR conflict events per 7 DUR screening modules (drugdrug interaction, therapeutic duplication, allergy, dosing, disease contra-indication, geriatric contra-indication, pediatric contra-indication). Average rate of DUR modules usage in 2008 (After) were 0.72. Average number of prescription drug per patient were reduced from 5.6 (Before) to 3.8 (After), and DUR program seemed to effect positively on physician's prescription related decision process. Overall DUR conflict events occurred by 8 physicians for 3 months were 17,923 Before and 20,057 After DUR program, and DUR conflict events per prescription were 2.8 Before and 2.9 After, respectively. Therapeutic duplication (37%), geriatric contra-indication (34%) and dosing (18%) were high ranked DUR conflicts. As the study was not sufficient to show a consistent trend to reduce DUR conflicts After, another study to confirm it's effectiveness would be recommended. This study would be of help to develop awareness of DUR program to healthcare providers.