Background: Knowledge about diabetes mellitus affects on lifestyle of patients having diabetes mellitus. Knowledge is one important factor that determines health management for sufferers. Purpose: Purpose this study almed to determine the relationship between level knowledge of diabetes mellitus (DM) management of fasting blood sugar level (GDP). Method: This study uses a quantitative cross sectional method with a correlation approach. Respondents in this study amounted to 68 people by sampling using purposive sampling. Measurement of level knowledge of DM management uses a questionnaire, and measurement of value GDP using the glucose test tool (easy touch). Data analysis has been done by using univariate analysis and bivariate analysis. The study was conducted in January – February 2019. Results: Based on statistical test table showed correlation coeffisien that is -0.422 with value Significant (ρ) that is 0.000 which show that value of ρ<0.05. Conclusion: There is a relationship with moderate closeness between the level of knowledge of DM management with fasting blood sugar levels (GDP).