OBJECTIVES: Accurate estimates of years of life lost (YLLs) are necessary to assess the management of diabetes mellitus (DM) and to understand the burden of the disease on society. We aimed to quantify the impact of mortality because of DM by estimating the YLLs in Colombia between 1979 and 2017. METHODS: An ecological study was conducted using mortality data from the National Administrative Department of Statistics of Colombia. YLLs attributable to DM and trends in the rates of YLLs by sex and age group were estimated using Joinpoint Regression. Forecasts of YLLs because of DM were performed using autoregressive integrated moving average models. RESULTS: Between 1979 and 2017, 200 650 deaths were registered, whose basic cause of death was DM. Up to 69 years of age, it was observed for both sexes that the older the age group, the higher the proportion of YLLs. The trend of the adjusted rate of the YLLs estimated for DM increased between 1979 and 2000 to 2001 and later decreased more sharply among women, and the reduction was high for the 65 and over age groups. The 2018 to 2025 YLL rates for DM in Colombia are predicted to have the highest values in the total series in April 2024 (13 514/1000 population). CONCLUSIONS: In Colombia, between 1979 and 2017, the YLLs and age-adjusted rates of YLLs because of DM showed a slight decrease in both men and women.