Temperature and salinity are important factors that affect several physiological processes in aquatic organisms, which could be produced by variation of certain hormones. In this study, the expression of pituitary hormones involved in the acclimation to different temperatures and salinities was examined in Sparus aurata, a euryhaline and eurytherm species, by Q-Real Time RT-PCR and Western blot analyses for mRNA and protein expression, respectively. Three different experimental conditions were designed with specimens (10 per treatment) acclimated to: a) low salinity water; b) sea water; and c) high salinity water. Additionally, fish under different salinities were acclimated to three different temperatures: 12, 19 and 26 degrees C. Animals were maintained seven weeks before sampling pituitary glands. Our results provided enough evidence for a differential expression of PRL, GH and SL in the pituitary of gilthead sea bream, under different temperature and salinity regimes.