The invention relates to a beta-cyclodextrin-modified polyamide-dendrimer and a preparation method of a gold nanoparticle compound of the beta-cyclodextrin-modified polyamide-dendrimer. The preparation method includes: mixing DMSO (dimethyl sulfoxide) solutions in which beta-CD and CD I are dissolved, respectively, adding DMSO solution of G5PAMAM after reacting, performing stirring at room temperature for 3 d, and performing dialysis and freeze-drying to obtain G5.NH2-beta-CD; adding HauCl4.4H2O solution into the obtained G5.NH2-beta-CD solution, adding NaBH4 solution after stirring, performing stirring for 2-4 h, and performing dialysis and freeze-drying to obtain a target compound {(Au0)25-G5.NH2-beta-CD}. The prepared compound is a good gene carrier, capable of successfully carrying and expressing pDNA-transfected human embryonic kidney cells, transfection conditions are mild, operating is easy, transfection efficiency is high, and the compound has a promising application in terms of biomedicine such as gene therapy.