We conducted a prospective study with the aim to evaluate the efficacy and safety of standardized cranberry capsules as prophylaxis in children with recurrent Urinary Tract Infections (UTIs). Therefore, children and adolescents, aged 2-18 years, with history of recurrent UTIs, were recruited for the study and randomized to receive cranberry in a standardized dose of cranberry extract 125 mg (proanthocyanidins 7.2%), vitamin C 7.5 mg and vitamin E 2.5 mg or not. They were followed for 1 year during which compliance, side-effects and UTI episodes were recorded. Children on cranberry compared to control group presented significantly lower percentage of UTIs, fewer days/year on antibiotic treatment and lower percentage of initiation of antimicrobial prophylaxis (p<0.05) due to UTIs recurrences. In addition, in the subgroup of children with vesicoureteral reflux we observe a significant difference between the cranberry and the controls group in the number of UTIs (p<0.05). No side effects in cranberry group were reported. Escherichia coli, Klebsiella and Proteus spp. in this order were the predominant species isolated in both groups in the beginning and also in the end of the study. A trend of decrease of E. coli episodes in the cranberry group before and after the treatment was documented (83.3% vs. 66.6%), however, this was not significant (p=0.28). It seems that the use of standardized dose of cranberry seems to be a secure and effective treatment for children with recurrent episodes of UTIs