An 8-year-old boy presented with precocious puberty and hypertension. He had hypokalemia, increased serum aldosterone and testosterone levels and low plasma renin activity. An adrenal adenoma was found using imaging methods and was removed. Postoperatively aldosterone, testosterone and blood pressure returned to normal. Renal ultrasonography findings were consistent with nephrocalcinosis, which might be explained by long lasting hypokalemic metabolic alkalosis and hypercalciuria. Precocious pseudopuberty progressed into true puberty due to the maturational effect of testosterone. Nephrocalcinosis was still present 8 years later and hypertension was recurring obviously as a consequence of increased peripheral resistance.