Diabetes mellitus is the result of complex interactions involving many genes and environmental factors, and rapid socio-environmental changes have been strongly associated with the development of diabetes. In this study, we examined the trends in diabetes mortality and associated socio-environmental changes that have occurred in South Korea over the last 20 years. Data from a national database and government reports for the years from 1983 to 2001 were analyzed. The data included mortality, socio-economic changes, physical activity and dietary pattern indicators. Deaths from diabetes per 100,000 people increased from 5.3 in 1983 to 18.4 in 2001. Along with increasing diabetes-related mortality, many socio-economic indices (gross domestic production, proportion of tertiary industry and urbanization rate), proxies for physical activity (numbers of cars and time spent watching television) and diet indices (animal protein intake and fat intake) showed remarkable changes. To counter increasing prevalence of diabetes and its related mortality in South Korea, multidirectional efforts including lifestyle modification should be mandatory features of future public health policy.