This study was to evaluate economic impact of a comprehensive pharmaceutical care intervention provided by community pharmacists on drug-related morbidity and mortality in the elderly population, in a societal perspective. Clinical outcomes of pharmaceutical care included compliance increase, inappropriate medication discontinuation, and subsequent drug-related morbidity and mortality reduction. Economic outcomes included cost savings from direct medical costs reduction such as medication and healthcare resource utilization. Input costs for pharmaceutical care included pharmacist time and computerized prescription review supporting program costs. Model parameters of outcomes were derived from published literatures, and costs were from literatures and health insurance statistical data in Korea. Annual costs and benefits were estimated in the year 2005. Current usual care and standardized pharmaceutical care required 0.3 and 2.0 hours per year respectively, for elderly outpatient using average 4.4 prescription drugs per visit and average annual frequency of 17.8 pharmacy visits. Comprehensive pharmaceutical care provided to overall elderly outpatients at community pharmacies would have cost of 74,994 mil. and benefit of 357,002 mil. per year. Benefit:cost ratio was 4.8:1 and net benefit was 282,008 mil/year. It was corresponded to net benefit of 73,816/year for individual elderly patient. In addition, pharmaceutical care was estimated to reduce 1,531 drug-related deaths/year. Conclusively this study, a first attempt in Korea to evaluate an economic value of pharmaceutical care at community pharmacies, proved that it was a cost-effective intervention having significant economic benefit.