OBJECTIVE To describe the long-term outcome of surgical conservative treatment of bladder endometriosis. METHODS Descriptive study. METHODS Tertiary referral center for the treatment of endometriosis. METHODS Forty-seven patients with symptomatic bladder endometriosis. METHODS Partial cystectomy by laparoscopy or laparotomy. METHODS Rates of recurrence at a 36-month follow-up. RESULTS All 14 patients with isolated bladder dome lesions remained symptom-free. Among the 33 patients with lesions involving the vesical base and vesicouterine septum, cumulative recurrence rates at 36 months were 24.7% and 15.5% for recurrence of symptoms and of clinical-instrumental evidence of lesion, respectively. The only factor influencing rate of recurrence was the extent of surgical excision. When the resection included both the vesical lesion and a 0.5- to 1-cm deep portion of the adjacent myometrium, recurrence was significantly less frequent compared to the removal of the bladder lesion only (7% vs. 37% for symptom recurrence and 0% vs. 26% for clinical-instrumental recurrence, respectively). CONCLUSIONS Conservative surgical treatment of bladder endometriosis seems effective in ensuring long-term relief in almost all cases of endometriosis affecting the vesical dome, whereas success rates for deeper lesions involving the vesical base and the vesicouterine septum are lower, depending on the degree of surgical radicality.