Various biological and artificial materials have been introduced for endoscopic treatment of vesicoureteral reflux. Over the past years, dextranomer combined with hyaluronic acid (Dx/Ha) has been established as the most commonly used tissue-augmenting substance for subureteral injection because of its biocompatibility. Nevertheless, the histopathologic analysis of failed Dx/Ha injections showed changes in consistency and volume of the deposit and granulomatous reactions of the adjacent tissue. We report a case of late-onset obstruction 2 years after the injection of Dx/Ha. In the current literature, this potential long-term complication is hardly mentioned.