A longitudinally coupled resonator acoustic wave filter device that utilizes an inter-IDT resonance mode with a reduced insertion loss has a structure in which apodization weights are assigned in first to third IDTs having narrow pitch electrode finger portions in portions other than the narrow pitch electrode finger portions, such that the electrode finger overlap width sequentially varies in an acoustic wave propagating direction in which an acoustic wave propagates, and portions of the IDTs located at ends adjacent to the narrow pitch electrode finger portions have a maximum electrode finger overlap width.