Purpose: To determine the value of interventional ultrasound (US) for adrenal masses, especially incidentally discovered adrenal masses. Methods: Demographic, clinical, and pathological data were reviewed for eight patients who underwent percutaneous US-guided puncture or biopsy for adrenal masses from September 1994 through March 2002 in our institute. Results: US-guided intervention was successfully performed for seven patients: two with adrenal cysts, two with adrenocortical adenomas, and three with metastatic adrenal tumors (one from prostate cancer, one from lung cancer, and one from renal cell carcinoma). The remaining patient had bilateral adrenal masses, and a biopsy specimen could not be obtained because safe puncture was difficult. For all patients there was no postoperative hemorrhage or pain, and no major complications were observed during the procedure. Conclusions: Interventional US using the color Doppler method for adrenal masses is a useful procedure for safe puncture to reveal the orientation of adjacent viscera and blood vessels at the puncture site and to avoid complications including hemorrhage and pneumothorax. US, including color Doppler US, is also useful for detection of complications and follow-up studies because it is noninvasive and can be used for real-time examinations. In addition, pathological examination of specimens obtained by percutaneous biopsy or fine needle aspiration is useful for avoiding unnecessary surgery in patients with metastatic adrenal masses.