Testicular adrenal rest tumours (TART) are aberrant adrenal tissue within the testes (1). Although benign, they can lead to obstruction of the seminiferous tubules and infertility in patients with congenital adrenal hyperplasia (CAH). We report six boys who developed TART, a complication of CAH. Diagnosis was confirmed by ultrasound and testicular vein sampling of elevated 17-hydroxyprogesterone (17-OHP) levels. Glucocorticoids dosages were increased 1½-2 folds to suppress size of the aberrant adrenal tissues. Despite reductions in 17-OHP, the lesions remained unchanged. Three patients had testis-sparing surgery to excise the TART and to preserve normal testicular tissues.