Background and aims: to develop a prognostic mathematical model for risk of microangiopathy in patients with diabetes mellitus type 1 (T1DM). Materials and methods: 62 T1DM patients were divided into 2 groups according to НвА1с level: group 1 (n=18) with НвА1с ≤ 7.0% and group 2 (n=44) with НвА1с > of 7.0%. HbA1c, Cpeptide, blood creatinine, estimated glomerular filtration rate (eGFR) CKD-EPI, first morning urinary albumin excretion (AU) were determined. Blood glucose levels were conducted by CGMS (Continuous Glucose Monitoring System). All patients were followed for 3 months. Rank correlation method was used. Results: We established the direct correlation between HbA1c the AU level ρ=0.29 (р<0.016) at the beginning and ρ=0.4 (р=0.021) after 3 months. AU level has a direct correlation with blood glucose range, at the beginning ρ=0.51 (р<0.001) and after 3 months ρ=0.48 (р=0.004) visits. We made the mathematical description of this dependence. Each additional unit of blood glucose range is accompanied by increasing an average level AU level by 0.4816 mg/l. Conclusion: our mathematical equation of dependence between AU level and blood glucose range gives the opportunities to predict diabetic kidney disease progression in T1DM patients.