Obstructive nephropathy refers to a kidney disease caused by obstruction of urine flow in the urinary tract, which produces backward pressure and affects the normal physiology of the renal parenchyma. The degree of obstruction can be complete or partial; the range can be bilateral or unilateral; the time can be acute or slow and gradual; the location can be the upper urinary tract and the lower urinary tract; the upper urinary tract is above the ureter-bladder junction (ureter, renal pelvis, ureter-pelvis junction); the lower urinary tract is below the ureter-bladder junction (urethra, bladder neck, bladder-ureter junction). The impact on the kidney is related to the degree and time of obstruction. Early removal of the obstruction can make the lesions disappear, while late-stage obstruction can cause permanent and irreversible loss of renal function.