Longitudinally coupled resonator-type surface acoustic wave filter

Disclosed is a surface acoustic wave filter comprising two or more IDTs arranged in a propagation direction of the surface acoustic wave, wherein said two or more IDTs include at least one pair of IDTs arranged adjacent to each other in order to be acoustically coupled to each other, and have different numbers of paired electrode fingers, and a pitch between each neighboring two of almost all of the electrode fingers included in one of the pair of IDTs which has the smaller number of paired electrode fingers is made different from one to another in order that the IDTs should include no primary pitch area.