Van Wyk Grumbach syndrome refers to the development of peripheral precocious puberty, long-standing hypothyroidism, and gonadal masses; when not diagnosed, an unnecessary gonadectomy may be done; Here we present a case of a 10-year-old girl with Down syndrome, short stature, and vitiligo presented with vaginal bleeding, and a pelvic mass, in whom bilateral gonadectomy was performed. Most cases of Van Wyk Grumbach syndrome present in women, and classic hypothyroidism symptoms always precede the diagnosis; 11% of patients have Down Syndrome, sometimes tumor markers get elevated, and some develop severe symptoms (myopathy, short stature, mental delay, ascites, pericardial effusion, Cullen sign, pituitary hyperplasia, and severe anemia), that respond to levothyroxine treatment; Conclusions: Children with peripheral precocious puberty and gonadal masses, must be studied for hypothyroidism before any radical decision is made. Keywords: Puberty, Precocious; Ovarian Cysts, gonadectomy, Van Wyk Grumbach Syndrome