In the past decade, the importance of the kisspeptin system in reproductive development and its pivotal role in the regulation of the reproductive endocrine axis has become clear. The kisspeptin system has roles in the onset of puberty, the control and regulation of sex steroid production, and regulation of fertility and reproductive function. However, the exact functions of the fish kisspeptin system are not well understood, especially their potential local roles in the gonads. Thus, the goal of my study was to characterize the expression of the kisspeptin genes (kiss1, kiss2, and the receptors kiss1ra and kiss1rb) in the marine teleost Anoplopoma fimbria (sablefish), and explore their possible gonadal functions during sex differentiation (i.e. the formation of the ovaries versus testes) and subsequent gonadal development. Using several molecular techniques, including standard, semi-quantitative, and quantitative PCR, and in situ hybridization (ISH), I revealed that kiss2 and kiss1rb are the most highly expressed of the sablefish kisspeptin genes and both show sexually dimorphic expression in the gonads. Specifically, kiss2 shows significant increases in gonadal expression during ovarian development and the receptor, kiss1rb, exhibits a similar expression profile. Localization of these mRNAs within the sablefish ovary by ISH demonstrated that they are both highly expressed in the cytoplasm of oocytes. Thus, my results suggest that Kiss1rb is the putative receptor for Kiss2 and that Kiss2 plays a role locally in ovarian development, but not sex differentiation. In the future studies, I hope to determine the specific function of the gonadal kisspeptins. If kisspeptins do have a role in early ovarian development, this system could be important to future studies on reproductive dysfunction that occurs in captive female sablefish and some other fishes.