Background <p>Predicting the success of endoscopic treatment of VUR in transplant patients may not only protect both the physician and the patient from unnecessary investigations and treatment but may also prolong the life of the graft by preventing possible loss of time.</p> Methods <p>This retrospective study included 116 patients with vesicoureteral reflux following kidney transplantation between 2014–2022. Demographic data, preoperative and intraoperative clinical aspects, and postoperative 6^th-month success rates were evaluated.</p> Results <p>The success rate of the injection treatment in the 6^th month was 41.4%. As the patient age decreased, the success rate of the injection decreased (<i>p</i> = 0.025). While no significant relationship was observed between the preoperative reflux grade, injected volume of the bulking agent, and success (<i>p</i> = 0.109 and 0.222, respectively), a significant decrease in success was observed with an increase in UDR (<i>p</i> &lt; 0.001) in group comparison. Regression analyses demonstrated that pre-injection visual assessment and post-injection orifice mound view influenced the success rate (<i>p</i> &lt; 0.001 and <i>p</i> &lt; 0.001, respectively).</p> Conclusions <p>Intraoperative visual assessment of the orifice is a reliable indicator for predicting the success of subureteric injection. It not only provides patients with trustworthy postoperative information but also saves clinicians time by anticipating the next surgical stage, ultimately contributing to the prolongation of graft life.</p>