There is provided a sound-insulation material for a vehicle, that can reduce the weight thereof and exhibit sufficient sound insulation performance against noise of 500 Hz to 6400 Hz generated in vehicles. The sound-insulation material for a vehicle, of the present invention, includes: a core layer 10 having tubular cells 20, the tubular cells being arranged in a plurality of rows; an airflow-blocking resin film layer 40 provided on one surface of the core layer; and a decoupling layer 30 provided on the airflow-blocking resin film layer 40, wherein: the cells have closed surfaces 21 and open ends 22 in every other row at cell ends on one surface of the core layer; at cell ends on the other surface of the core layer, the cells have open ends in the rows where the cells have the closed surfaces at cell ends on the one surface, and have closed surfaces in the rows where the cells have the open ends at cell ends on the one surface; open ends of the cells each allow an internal space of the cells to be in communication with an outside; and an average (P/v)/Za is 2.8 to 10 between 500 and 6400 Hz, where: P and v are respectively a sound pressure and a particle velocity on a surface of the airflow-blocking resin film layer provided on the core layer, the surface being opposite to the core layer; and Za is an acoustic impedance of the decoupling layer.