Albright's hereditary osteodystrophy (AHO) is a rare inherited disease characterized by skeletal abnormalities, short stature, and, in some cases, resistance to parathyroid hormone, resulting in pseudohypoparathyroidism (PHP). Heterozygous inactivating mutations of the GNAS1gene are responsible for reduced activity of the alpha subunit of the Gs protein (G_Sα), a protein that mediates hormone signal transduction across cell membranes. G_sα is also known to have oncogenic potentials, leading to the development of human pituitary tumors and Leydig cell tumors. Here, we report the 1st case, a 3.5-year-old girl, with classic AHO phenotype and PHP type 1A associated with a cerebellar pilocytic astrocytoma. Coincidence or genetic relationships of both diseases are discussed according to molecular findings and current literature.