PURPOSE: The laparoscopic adrenalectomy (LA) has become the preferred procedure for adrenal tumors since it has many advantages; a more rapid and comfortable recovery, shorted hospitalization, and fewer complications. The purpose of this study was to report the initial 4 years experiences of LA and describe the unusual findings encountered during the operations. METHODS: From February 1997 to November 2000, a total of 20 LA were performed. Several techniques of LA have been described already. We prefer the transabdominal approach in the lateral decubitus position using 3 or 4 trocars. RESULTS: 20 patients had all unilateral tumor. The pathological findings were 11 aldosteronomas, 6 Cushing adenomas, 2 pheochromocytomas and 1 cortical carcinoma. 18 cases of 20 patients were successfully operated by laparoscopic procedure and 2 cases were converted to open adrenalectomy. The reasons of conversion were sudden cardiac arrest due to unknown origin and intraoperative bleeding due to periadrenal massive fat. During the laparoscopic operation, 2 patients showed abnormal EKG findings. The pathologies of those patients were non-catecholamine-secreting cortical adenomas. After operation, they have been completely normal in EKG. The average operating time for the complete laparoscopic adrenalectomies was 186 minutes in the first 9 cases and 132 minutes in the next 9 cases. The first oral intake was started within 24 hours in all cases. There was no postoperative complication and no operative morbidity or mortality. The average hospital stay was 6.2 days in the first 9 cases and 4.2 days in the next 9 cases. CONCLUSION: The LA is relatively fast and safe method and is accepted as the preferred procedure for the adrenal tumors but it should be well prepared perioperatively. Surgeons and anesthesiologists should be aware of those possible cardiovascular complications and of the problems inherent in the manipulation of the adrenal gland during LA.