PURPOSE We compared the clinical outcomes of retroperitoneoscopic and open adrenalectomy for pheochromocytoma. MATERIALS AND METHODS Clinical data on 56 patients who underwent retroperitoneoscopic lateral adrenalectomy were retrospectively compared with those on 50 who underwent open adrenalectomy for pheochromocytoma, including patient demographic data, perioperative indexes and clinical outcomes. RESULTS Demographic data on patients were similar in the 2 groups. In the retroperitoneoscopic group such perioperative indexes were significantly different from those of the open group (each p <0.05), including operative time (mean +/- SD 52 +/- 22 vs 120 +/- 42 minutes), estimated blood loss (74 +/- 34 vs 187 +/- 64 ml), resumption of oral intake (1 vs 2 days), postoperative hospital stay (5.2 +/- 1.7 vs 8.3 +/- 1.8 days), incidence of intraoperative hypertension (17.0% or 9 of 53 patients vs 36.0% or 18 of 50) and number of patients requiring blood transfusion(1.8% or 1 of 53 vs 16.0% or 8 of 50). The incidence of systemic inflammatory response syndrome was much less in the retroperitoneoscopic group (20.8% or 11 of 53 patients vs 42.0% or 21 of 50, p <0.05). However, the duration of systemic inflammatory response syndrome and postoperative complications were similar in the 2 groups (p >0.05). Blood pressure returned to normal 3 months after the operation in 81% of the patients in the retroperitoneoscopic group and in 84% in the open group. During the followup of 5 to 36 months no tumor recurrence and/or metastasis developed. CONCLUSIONS Compared with open surgery retroperitoneoscopic lateral adrenalectomy for pheochromocytoma is a safe, minimally invasive and effective procedure.