Diabetic nephropathy is major long-term complication of diabetes mellitus a social and civilization-related disease. At present, the most sensitive and non-invasive indicator of the progression of diabetic nephropathy is microalbuminuria. Morphological features such as accumulation of extracellular matrix proteins, thickening of glomerules' basement membranes are prior to microalbuminuria. The aim of our clinical study was to establish whether urine and serum TGF-beta 1 and IL-6 levels may be significant in prognosing and evaluating a risk for developing diabetic nephropathy. The trial was carried out in 68 patients with type II diabetes mellitus and a group of 10 healthy subjects served as control. Urine and serum TGF-beta 1 concentrations were evaluated, as well as, basic laboratory parameters. After one-year-observation serum creatinine level and microalbuminuria value were investigated in 60 patients with type II diabetes mellitus. In patients with type II diabetes mellitus both urine and serum TGF-beta 1 and IL-6 were elevated. After one-year-observation of patients with type II diabetes mellitus it was established that the increase of serum creatinine concentrations values were higher in those patients, whose initial TGF-beta 1 levels exceeded normal values. A positive correlation between urine TGF-beta 1 level and the progression of renal failure measured by the increase of serum creatinine level was observed. In conclusion, our findings indicate that urine TGF-beta 1 and IL-6 levels may be a good prognostic factor of the development of diabetic nephropathy in the course of diabetes mellitus.