A unique case of 17 alpha-hydroxylase deficiency with steroid-responsive primary hyperaldosteronism is reported. Initially the patient was misdiagnosed as testicular feminization for 16 years and was thought to have typical primary hyperaldosteronism for 5 years. However, careful detailed endocrine studies showed markedly elevated progesterone, deoxycorticosterone, and 18-hydroxycorticosterone values with low levels of 17-hydroxyprogesterone, 11-deoxycortisol, testosterone, and DHEA-Sulfate. In contrast to the suppressed aldosterone levels that are found in 17 alpha-hydroxylase deficiency, this patient's aldosterone levels were inappropriately elevated before and after ACTH stimulation. Use of glucocorticoid replacement resolved the patient's symptoms and completely corrected the hypokalemia and hypertension. In summary, recognition of 17 alpha-hydroxylase deficiency with steroid-responsive primary hyperaldosteronism is important because hypertension, hypokalemia, and symptoms respond to steroid replacement.