The invention discloses novel 
growth hormone releasing 
hormone analog peptides and an application thereof in preparing medicines for treating 
infertility. Experiments discover that 2D, 2E or 2F 
peptide has obviously high hypophysis GH releasing activity and hypophysis 
hormone releasing specificity. Tested by the conjugation reaction of an in-vitro GHRH 
dimer peptide and a hypophysis GHRH 
receptor, 2D, 2E and 2F 
dimer peptides have extremely high hypophysis 
receptor binding activity, wherein the 2F 
dimer peptide has the maximum binding activity. With the 2F peptide as the representative, 
infertility model treatment finds out that, compared with a normal 
saline group and a pure 
cyclophosphamide control group, in the 2F dimer peptide group, the spermatocytes and the spermatogonia in the seminiferous tubules are obviously increased, the seminiferous 
tubule cells are arranged in order and large in volume, the cavities of the seminiferous tubules are reduced and even disappear, and 
dose dependency is shown. All the facts indicate that the GHRH peptides with the 2F peptide as the representative have an obvious effect of stimulating the proliferation and the maturation of spermatogonia / oogonia, thereby promoting 
reproduction; and as a result, the novel 
growth hormone releasing 
hormone analog peptides can be applied to medicines for treating 
infertility.