An acoustic wave device includes a piezoelectric layer, a first electrode, a second electrode, a first divided resonator, a second divided resonator, and a support substrate. The support substrate includes first and second energy confinement layers. The first energy confinement layer at least partially overlaps with a first region of the piezoelectric layer. The second energy confinement layer at least partially overlaps with a second region of the piezoelectric layer. The first and second energy confinement layers are integrally provided in the support substrate.