The invention discloses an intelligent macromolecular bonding drug for bonded cell penetrating peptides and a preparation method thereof. The macromolecular bonding drug takes polylactide as a main chain, a polyethylene glycol hydrophilic branch is introduced through carbon-nitrogen double bonds with pH response, and meanwhile, an anti-tumor drug and the cell penetrating peptides are grafted. According to the preparation method of the intelligent macromolecular bonding drug, oligomeric polyethylene glycol monomethyl ether with pH responsiveness, the cell penetrating peptides C-TAT and the anti-tumor drug are bonded onto a degradable polymer through sulfhydryl-ene click reaction, so that the macromolecular bonding drug is obtained, which can de-protect the oligomeric polyethylene glycol monomethyl ether in a weakly-acidic environment outside tumor cells to make the cell penetrating peptides to greatly increase the ability of the drug to reach the tumor interior and improve the drug delivery efficiency. The preparation method is mild in conditions, simple and convenient to operate, and large and controllable in drug loading capacity.