A 16-year-old man presented with severe nephrotic syndrome complicated by massive perirenal fluid. Percutaneous drainage of fluid was performed 3 times, followed by improvement in renal function and hypertension, but perirenal fluid recurred within days. Nephrotic syndrome was unresponsive to steroid therapy. A laparoscopic bilateral fenestration of Gerota's fascia and peritoneum allowed permanent drainage of fluid into the peritoneal cavity. During the same procedure, a renal wedge biopsy was performed. Histological examination showed advanced focal glomerular sclerosis of the tip lesion variant. The glomerular disease was refractory to further treatment with cyclophosphamide, mycophenolate, and rituximab. However, perirenal fluid did not recur despite persistent nephrotic syndrome, showing that fenestration of Gerota's fascia is a successful treatment of floating kidneys in such patients.