A method for adjusting frequency of a surface acoustic wave device includes performing a frequency adjustment. The surface acoustic wave device includes a substrate including at least one of a lithium tantalate substrate, a lithium niobate substrate, and a lithium tetraborate substrate. The surface acoustic wave device further includes an IDT electrode formed on the substrate that excites a pseudo-longitudinal leaky surface acoustic wave. The performing includes frequency adjustment by adjusting a thickness of the substrate at a side opposite in a thickness direction to a side on which the IDT electrode is formed.