The yellowtail kingfish (Seriola aureovittata) is a large, fast-swimming fish species characterized by high and aggressive feeding activity, rapid growth rate, and tender flesh. Feed intake is a key factor influencing fish growth and production performance, and appetite is a major determinant of feed intake. To explore the role and potential mechanisms of orexin and its receptor ox2r in the regulation of feeding behavior in S. aureovittata, this study employed homologous cloning to obtain the open reading frame (ORF) sequences of the orexin and ox2r genes in S. aureovittata. Quantitative real-time PCR was used to analyze the expression characteristics of these genes across various tissues and developmental stages, as well as their regulatory roles in response to starvation and subsequent refeeding.