Hypothalamic-Pituitary-Somatotropic (HPS) axis contains essential endocrine factors and plays diverse roles in the growth of teleost living in dynamic aquatic environments. In this study, 43 HPS axis genes were characterized in Chinese sea bass (Lateolabrax maculatus), the economically important marine fish highly adaptable to a wide range of temperatures and salinities. The phylogeny, conserved domain, molecular evolution and expression of L. maculatus HPS axis genes revealed their evolutionary conservation, with examples of functional divergence in duplication-originated genes (sst1a/1b, igf1ra/1rb). Weighted gene co-expression network analysis (WGCNA) among L. maculatus tissues revealed strong co-expression of HPS genes (ssts, igf1rs, igfbps) in brains than in livers and muscles, interacting with feeding (cartpt, negr1), metabolism (grik3, drd4), and growth (apba1) functional genes. Under temperature changes, L. maculatus HPS genes were more actively regulated in brains than in livers and muscles, with the hypothalamic and pituitary HPS genes mainly regulated in brains, whereas the peripheral HPS genes were regulated in livers and muscles. WGCNA revealed that HPS axis mainly interacted with stress and feeding activity in brains of L. maculatus under temperature stress, while it interacted with metabolism and growth activity in livers and muscles. Similar co-expression of HPS genes (sstrs, igf1rbs, igfbps) were with feeding (pik3r4), metabolism (mrps, ndufa12) and growth (sulf2, peli3, apod) functions in brains, indicating that HPS axis could regulate growth through coordinated mediation of the food-intake and energy metabolism in L. maculatus under environmental stress. Our results provided comprehensive understanding about the L. maculatus HPS axis responding to environmental stimuli, which are crucial for the growth regulation and will provide important insights into fast-growing L. maculatus cultivation.