Cystic cystitis is a separate form of urinary bladder inflammation, detected by cystoscopy in children with recurrent urinary infections. Cystoscopy is an invasive method, so the aim of this investigation was to determine the ultrasonographic characteristics of cystic cystitis and to assess the reliability of ultrasound in relation to cystoscopy in diagnosing cystic cystitis. The study included 115 girls with repeated urinary infections. Cystoscopy and ultrasonography was performed in all. According to the cystoscopic finding the subjects were divided into 4 groups. Lateral and posterior urinary bladder wall thickness was measured during ultrasonography. A statistically significant difference was found between all 4 groups, the method demonstrated a high degree of sensitivity (0.97) and specificity (0.91). Percentile calculations were determined for wall thickness. Ultrasonography can replace endoscopy in diagnosis and follow-up of cystic cystitis in children, with at least 50% fullness of the urinary bladder as a prerequisite.