According to one embodiment, a sound image localization apparatus includes following units. The first signal generating unit is configured to generate a first acoustic signal. The first speaker is configured to generate a first sound according to the first acoustic signal. The input unit is configured to input a localization magnification n. The first control filter unit is configured to adjust the first acoustic signal with a first control filter G1 calculated based on the input localization magnification n to generate a first adjusted acoustic signal. The second control filter unit is configured to adjust the first acoustic signal with a second control filter G2 calculated based on the input localization magnification n to generate a second adjusted acoustic signal. The second and third speakers are configured to generate second and third sounds according to the first and second adjusted acoustic signals, respectively.