Gene therapy using mRNA has facilitated progress in cancer therapy. However, its application is hindered by a limited tumor-targeted delivery approach, leading to off-target effects and safety concerns. Chimeric antigen receptor (CAR) molecules enable T cells to recognize specific antigens in a major histocompatibility complex-unrestricted manner. CAR approaches provide an "off-the-shelf" solution for introducing additional targeting functionality to a cell membrane. Cancer cell membrane-coated nanoparticles with homotypic tumor-targeted properties provide a readily accessible platform for gene engineering and membrane extraction. Herein, we demonstrate a CAR-inspired cancer cell membrane-coated platform for delivering an mRNA formulation through a dual tumor-targeted mechanism. The simplified human epidermal growth factor receptor 2 (HER2)-specific CAR molecule (comprising an extracellular HER2-binding domain, a hinge, and a transmembrane domain) was engineered on the cell membrane of cancer cells to establish CAR-CT26 cells. The extracted CAR-CT26 membrane (CARM) was subsequently coated onto the lipid nanoparticle (LNP)-mRNA surface to form a CARM@LNP-mRNA complex. In vitro, the CARM-coated nanoparticles exhibited enhanced mRNA transfection efficiency toward CT26 cells overexpressing target HER2 antigens. Systemic administration of the CARM@LNP-mRNA formulation resulted in stronger tumor-targeting ability and tumor suppression in HER2+ CT26 subcutaneous tumors and peritoneal cavity metastasis models than that observed with the CT26 cell membrane-coated version. Our data suggest that CARM@LNP is a feasible choice for mRNA-based gene therapy. These results provide evidence for the systemic administration of CARM@LNP-mRNA as a promising tumor-targeted therapeutic strategy.