To days,The Growth hormone (GH) gene is more important in the regulator of metabolism, osmoregulation, reproduction and skeletal growth in Livestock. GH almost in all of animals has been same function that mentioned. This hormone also is exciting skeletal cellular for more growth and replication. In Salmonids for specially, furthermore, GH gene in population of salmonids can be used as the studies of phylogenetics and  finding ancientand pedigree of salmonids that some researchers used from GH gene in salmo salar and salmo trutta for studies of phylogenetics.  In this study we had done sequence of fragments of GH gene in salmo trutta caspius full length of almost 2048 bp. and deposited in GeneBank (accession number, JN24163) For sequencing of GH gene in the Salmo trutta caspius, first was extracted DNA genomics from bloods and the muscles of salmons, in related to, we designed three pairs of primers from first to end of the GH gene in same sequences from salmo salar and salmo trutta that reported in GeneBank. After sequencing of fragments we analyzed fragments and compared with other sequences in salmonid fishes. In this research our aims, study of amount variation in the between salmo trutta caspius species with Atlantic salmon and also, study amount of phylogenetic variation between Salmo trutta caspius with other salmons regarding to the GH gene.