Urinary tract infection is the most frequent bacterial infection in children. Its prevalence in the population younger than 14 years of age has been estimated at 5–10%. Its high recurrence, especially in patients with risk factors, poses a significant problem. The risk factors most common in the group of children ≤3 years are congenital defects blocking the flow of urine to the bladder, whereas in older children they most typically include a tendency for constipation and dysfunction of the lower urinary tract. The clinical picture is variable and depends on the child’s age, immunity status, pathogen virulence and localisation of infection. The mildest form of urinary tract infection is asymptomatic bacteriuria, whereas more severe presentations include acute pyelonephritis, acute focal bacterial nephritis and urosepsis. Prognosis is usually good, but under certain circumstances hypertension, proteinuria and chronic kidney disease may develop. Therefore, early introduced appropriate treatment is essential. According to the Polish Society for Paediatric Nephrology guidelines, asymptomatic bacteriuria does not warrant treatment, whereas febrile patients (>38°C) under 24 months old with a suspicion for urinary tract infection must be promptly administered antibiotic therapy, after a urine specimen has been obtained for culture. For many years, urinary tract infection has remained a topic of controversy in terms of therapy duration and administration route. Inpatient treatment of children under 3 months of age is an accepted rule. Acute pyelonephritis necessitates a longer therapy, lasting from 7 to 10 days, whereas the duration of treatment of lower urinary tract infection has been cut down to 3 up to 5 days. Routine prophylactic antimicrobial therapy is not recommended following the initial urinary tract infection episode, yet should be considered in special circumstances. Alternative prophylactic methods, such as immunostimulating agents, probiotics or cranberry, may be used, but their efficacy has not been confirmed in large clinical studies.