An integrated nanosystem for liver-targeting co-delivery of gene/drug and a preparation method therefor, belonging to the field of biomedicine. Multiple functions have been integrated into one biocompatible and safe carrier, which comprises an copolymer moiety [poly(N, N-dimethylaminoethyl methacrylate) (PDMAEMA)] grafted with a poly(3-azido-2-hydroxypropyl methacrylate) (PGMA-N3)] component having pH stimulation response functions and being loaded with a nucleic acid/drug, a fluorescent-based imaging component Rhodamine B (RhB), and a galactose as a targeting ligand. The drug delivery system provided is safe and can have a synergistic effect in gene/drug therapy, being expected to play a huge role in clinical applications.