Abstract: Recent advancements in stem cell research have provided hope for treatment tools in patients with terminal diseases, such as Parkinson’s, Huntington’s, amyotrophic lateral sclerosis, and glaucoma. Although the absence of reproductive function is not a life-threatening condition, it is a serious problem for Idiopathic Hypogonadotropic Hypogonadism (IHH) patients, who do not have functional gonadotropin-releasing hormone (GnRH) neurons in the hypothalamus. Consequently, they are not able to conceive and need hormone treatments for their entire lives. GnRH is released from the median eminence of the hypothalamus into the portal circulation and stimulates pituitary LH and FSH release, which controls gamete production and gonadal steroid secretion. GnRH neurons originate from olfactory placode, rather than neural crest cells, and migrate into the preoptic area/hypothalamus during the embryonic stage. Knowing this developmental characteristic, we are successful in generating GnRH neurons from human embryonic stem cells as well as induced pluripotent stem cells. Generated GnRH neurons release the GnRH peptide in a pulsatile manner and respond to high potassium challenge, similar to release from the hypothalamus in vivo and primary GnRH neurons derived from monkey olfactory placode. Generated GnRH neurons from stem cells will be useful for future cell replacement therapy, disease modeling for abnormalities associated with GnRH neural dysfunction such as IHH, and contraceptive drug development.