Background: For tumours of the adrenal gland different surgical retroperitoneal approaches have been established, including the lateral and the dorsal approach. It is still unclear if the lateral or the dorsal approach should be preferred. Patients and Methods: A retrospective comparison between 21 patients who underwent retroperitoneoscopic adrenalectomy in lateral position (LRA) and 24 patients who underwent a retroperitoneoscopic adrenalectomy in dorsal position (DRA). Results: There were no significant differences with regard to the age, sex, tumour localisation, and the size of the tumour. The body-mass-index as well as the operation time was significantly higher of patients who underwent surgery in lateral position. Complications were comparable in both groups. Conclusion: The dorsal and the lateral retroperitoneal approach are ideal approaches for patients having had an intraabdominal surgery before. Due to the missing intraabdominal pressure the lateral approach is advantageous for patients with high body-mass-index (>35) and is indicated for patients with a tumour >6 cm due to the small retroperitoneal space.