Fluoroscopically guided, percutaneous antegrade pyelography in canine patients has been described previously in the veterinary literature. This report describes the technique with ultrasonographic guidance and its clinical application in the diagnosis of four cases (two dogs, two cats) of obstructive uropathy. The technique provided successful diagnosis of ureteral obstruction in all four cases. No complications were observed in three cases. In one feline case, ureteral obstruction with a blood clot occurred following the procedure; however, it could not be ascertained whether this event represented a complication of the technique.