PURPOSE: To obtain a surface acoustic wave device with a low loss provided with a structure able to suppress an undesired response at the outside of a pass band and to reduce an in-band ripple.

CONSTITUTION: In the section surface acoustic wave device 11 where plural interdigital transducers (IDT) 13-23 are arranged on a surface acoustic wave substrate 12 along the propagation direction of the surface acoustic wave and plural IDTs are used as an input IDT and an output IDT alternately in the direction of the surface acoustic wave propagation and the distance between adjacent IDTs is made different, the plural IDTs are arranged so as to satisfy equations I, II, where l1 is a distance of adjacent IDTs, l2 is a distance of other adjacent IDTs adjacent to the IDTs whose distance is l1 and L is a wavelength of the surface acoustic wave.