The evaluation of children with suspected blunt renal injury relies mainly on clinical assessment, urinalysis, and imaging studies. Because imaging studies rarely influence management, yet entail both risk and expense, we investigated a protocol to define their appropriate use. During a one-year period, children seen in the emergency department underwent a mandated radiographic evaluation for renal injury only if they had (a) severe injuries or (b) a urinalysis with greater than 20 RBC/hpf. Thirty-two children were enrolled; 16 had imaging studies that detected four abnormalities, ie, three contusions and one incidental finding of renal papillary necrosis. All children with abnormal imaging studies had greater than 20 RBC on urinalysis. None of the 16 children who were not studied radiographically developed complications related to renal trauma during short-term follow-up. Our findings support earlier recommendations for limiting the use of imaging for suspected blunt renal trauma in children with minor to moderate injuries and hematuria of less than or equal to 20 RBC/hpf.