We encountered a patient whose renal scintigram showed renal tubular damage four days after administration of contrast material for CT. As no secretion of radioisotope to the urinary tract was observed on the scintigram and the renogram did not show a secretionary phase, renal tubular damage was suspected. As the renal damage disappeared six days after administration of the contrast material, the damage seemed to be transient, disappearing within five days. Caution is needed with the use of renotoxic drugs such as anti-tumor drugs, especially within five days after administration of contrast materials.