Urinary tract infection (UTI) is a well recognized complication in malnourished children. The need to investigate these patients for underlying renal pathology has not been clearly defined. Seventy-five children with malnutrition were evaluated for UTI by culture of urine obtained suprapubically prior to antibiotic therapy. All patients with UTI were investigated with renal ultrasonography, intravenous pyelography (IVP) and voiding cystourethrography (VCU). Haemoglobin, white cell count, serum urea, creatinine and electrolytes were determined in all the children. The mean age of the children was 15.5 months (range 3-60 months). UTI was diagnosed in 26 (34.7%), of whom 21 (81%) were boys. The overall prevalence of UTI in those with kwashiorkor/marasmic kwashiorkor was 42%. Escherichia coli was the organism most commonly cultured (84.6%). Renal sonography, IVP and VCU were normal in all infected cases and vesicoureteric reflux was not detected in any. This study confirms the high prevalence of UTI in malnourished children. As no anatomical abnormalities were demonstrated in the patients with UTI, imaging of the renal tract other than real sonography does not appear to be indicated in the malnourished child in a first episode of UTI with normal renal function.