We describe two children who presented with extreme weight gain and failure to grow in height, and who were both diagnosed with Cushing's disease. Following preoperative metyrapone treatment, both children successfully underwent curative transsphenoidal surgery. While obesity is a common and increasing problem in childhood, Cushing's disease is rare. The combination of weight gain and growth failure in a child is an alarming sign in which underlying endocrine disease must be ruled out.