Immunocytochemical staining technique was used to study the expression of gonadotropin-releasing hormone (GnRH) in the nervous system and gonad of Coregonus peled. The results showed that there were GnRH immunoreactive endocrine cells in the cerebrum,cerebellum,diencephalon,medulla oblongata,and spinal cord.There were GnRH immunoreactive endocrine cells in the ovary and testis.The positive staining was observed mainly in the small growing oocyte,and in the interstitial cells and spermatogonia.The possible physiological function and morphological evidence of GnRH regulation on the development of gonad in C.peled were discussed.