Currently, there is increasing incidence of chronic kidney disease (CKD) caused by violation of the urine passage. Despite the practical importance of the problem, the issues of early diagnosis of renal parenchymal damage in patients with obstructive uropathy caused by benign prostatic hyperplasia (BPH) are still not fully understood. The aim of our work was to study laboratory parameters of renal damage in patients with BPH. Patients and methods. A clinical study was carried out on three groups of patients: patients without uro-nephrological diseases, BPH patients with residual volume of urine in the bladder, and BPH patients without residual urine. All patients underwent ultrasound examination of the kidneys and the urinary tract, the determination of residual urine volume, urinalysis, counting of cell elements in the urine with Nechyporenko test, determination of serum creatinine and urea, determination in urine total protein, albumin, the , γ-glutamyl transpeptidase (GGT) and the N-acetyl-β-glucosaminidase (NAG) activity, urinary cystatin C. Results. It was not found to increase the levels of serum creatinine and urea, as well as increased urinary total protein and urinary cystatin C in two groups of patients with BPH. leukocyturia and microhematuria was detected in the small proportion of patients in both groups. A microalbuminuria was brought out in considerable number of the patients of the two groups with BPH. 3—5 fold increase in urinary NAG activity was noted in the most cases BPH (in both groups). 2-fold increased activity of GGT in urine was noted in the group of patients with proven obstruction. Comments. Our study confirms damage to the renal parenchyma with partial obstruction of the lower urinary tract. The pathological value of kidneys injury indicators in the kidney were diagnosed at the large number of BPH patients with urinary obstruction. The above shows the development of the latent obstructive in some patients with BPH. We have to carry out in addition to standard laboratory tests revealing renal enzyme activity in urine (preferably NAG) and detection of microalbuminuria for early laboratory diagnosis and monitoring of patients with BPH CKD.