An acoustic wave device includes a silicon oxide film, a piezoelectric body made of lithium tantalate, and interdigital transducer electrodes stacked on a supporting substrate made of silicon, in which the values of the wave length-normalized film thickness and the Euler angle of the piezoelectric body made of lithium tantalate, the wave length-normalized film thickness of the silicon oxide film, the wave length-normalized film thickness of the interdigital transducer electrodes in terms of aluminum thickness, the propagation direction of the supporting substrate, and the wave length-normalized film thickness of the supporting substrate are set such that represented by Formula (1) for at least one of responses of first, second, and third higher-order modes is more than about −2.4, and TSi>20.