Diabetes is a leading cause of morbidity and mortality in Wisconsin and the United States. We examined mortality trends for diabetes as an underlying cause of death for the years 1979-1997 for Wisconsin and the United States. Diabetes mortality rates in Wisconsin have increased over the past 18 years, from 13.5/100,000 in 1979 to 16.7/100,000 in 1997. Much of this increase is attributable to a change in the death certificate in 1989. Blacks in Wisconsin have a higher rate of diabetes mortality when compared with whites, especially among women and persons less than 65 years of age. This disparity has increased markedly over the decade. Public health efforts in Wisconsin need to focus on reducing diabetes mortality overall and on minimizing disparities in diabetes mortality between whites and blacks.