The invention belongs to the fields of intelligent bionic materials, high-molecular materials and biomedical engineering, and concretely relates to a polydopamine particles-doped star-shaped polymer of a multi-responsive self-healing hydrogel, and the self-healing hydrogel and a preparation method thereof. In the present invention, the polydopamine nanoparticles and the star-shaped polymer SPDMAEMA-AA are prepared first; and the polydopamine nanoparticles, SPDMAEMA-AA and branched polyethyleneimine are mixed in proportion to form a crosslinked network by forming a dynamic reversible enamine bond through the acetoacetate on SPDMAEMA-AA and an amino group in the PEI molecules to obtain the hydrogel. The self-healing hydrogel material prepared by the invention has good near-infrared responsiveness, biocompatibility and high self-healing efficiency, and has potential applications in the fields of solid-state band-aids, drug slow release, cell culture, and a double-layer drive.