PURPOSE: The purpose of this study was to evaluate the feasibility, safety, and clinical effectiveness of ultrasound and fluoroscopy-guided percutaneous nephrostomy (PCN) placement in infants and young children. MATERIALS AND METHODS: Between January 2000 and December 2015, 57 patients had a total of 66 fluoroscopically guided PCN placement procedures. There were 37 boys and 20 girls with a mean age 8.6±15.3 (SD) months (range: 1 day-75.5months). The most common underlying disease was upper-urinary-tract obstruction, including ureteropelvic-junction stenosis (27/66, 40.9%) and ureterovesical-junction stenosis (16/66, 24.2%). Technical success, complications, clinical effectiveness, and radiation exposure were retrospectively analyzed. Technical success was defined as completion of PCN catheter in the renal calyx or proximal ureter. Complications were graded in severity using the Common Terminology Criteria for Adverse Event (version 4.03). Clinical effectiveness was evaluated with presence of decompression of the hydronephrosis on follow-up ultrasonography. RESULTS: All PCN placement procedures were technically successful. A total of 37 complications were identified in 33/37 procedures (89.2%), with transient gross hematuria (n=28) being most common (mean hematuria duration 2.2±1.4 [range: 1-6] days), which were grade 1 Postprocedural fever occurred after eight procedures; four and three patients were graded 1 and 2, respectively. Complete hydronephrosis decompression was achieved in 35/53 kidneys (66%), incomplete hydronephrosis decompression in 17/55 kidneys (32.1%), and progression of hydronephrosis was noted in 1/55 kidney (1.9%). Dose-area-product (DAP) was 44.86±89 (SD) (range: 3.7-464) µGycm2 and cumulative dose was 10.3±20.4 (SD) (range: 0.3-97.9) mGy. CONCLUSION: PCN is a feasible and effective treatment option to relieve urinary obstruction, and can serve as a bridging procedure until definitive corrective surgery in pediatric patients.