Congenital malformations of the ureter are common, accounting for 20% of all urinary system malformations. They are classified into malformations of the ureteropelvic junction, anomalies in the number of ureters, structural malformations, positional malformations, and malformations of the vesicoureteral junction. Clinically, they are often asymptomatic, but when symptoms are present, they are predominantly abdominal pain, hematuria, and urinary tract infections. Today, they are most commonly detected through prenatal ultrasound, but other important diagnostic methods include voiding cystourethrography, intravenous urography, DMSA scintigraphy, dynamic diuretic renography, computed tomography, and magnetic resonance imaging. Treatment is carried out using both conservative and surgical methods. Conservative treatment is based on antibiotic prophylaxis, while surgical treatment is chosen for symptomatic patients and those with impaired kidney function. It is crucial to timely recognize malformations that require treatment, as they can damage kidney function and negatively impact the patient's quality of life.