bACKgROUND: Tetrasomy X is a rare chromosomal aneuploidy seen in girls, associated with facial dysmorphism, premature ovarian insufficiency and intellectual disability. A Rathke's cleft cyst (RCC) is a remnant of Rathke's pouch which may cause multiple pituitary hormone deficiencies by exerting pressure on the pituitary gland in the sella. MeTHODS/ReSUlTS: The patient was diagnosed with tetrasomy X by karyotyping during infancy. brain MRI and multiple endocrine stimulation tests revealed RCC and combined pituitary hormone deficiency (growth hormone deficiency, secondary adrenal insufficiency and central hypothy-roidism) likely due to RCC. CONClUSION: We report the first case in the literature of a girl with 48, XXXX and combined pituitary hormone deficiency due to Rathke's cyst.