Twenty-one patients with non-visualized kidney on intravenous urography (IVU), whose ultrasound (US) examinations showed moderate to severe hydronephrosis (3 of them subjected to non-conclusive retrograde uretropyelography), were included in this study. All of them underwent percutaneous antegrade pyelography (PAGP) under US guidance at Radiology Department, Saddam Teaching Hospital, Basah, form January 2000 to January 2002. Ninty-five percent of them had satisfactory and conclusive results; nine cases with radiolucent stones, 5 with congenital pelvi-ureteric junction (PUJ) obstruction, 5 with ureteric strictures and one case with severe hydrocalyces and contracted pelvis that was proved to be tuberculosis of the kidney. On the other hand, the technique failed in one case. The study included 15 males and 6 females, their ages ranged between 12-71 years and the mean age was 45 years. No complication was recorded. We conclude that this procedure is a relatively simple, safe, and useful technique to visualize the renal collecting system in certain cases allowing the surgeon to choose a more suitable operative approach for that particular condition.