This diffracted sound reduction device (100) comprises the following: a reproduction speaker (101) that outputs reproduction sound that has the characteristics shown by an input signal; at least two control speakers (102) that reproduce a control signal that shows the characteristics of the control sound for reducing the sound pressure of the diffracted sound which is the reproduction sound that has reached each of a plurality of control points except for the position of the listener; and a control filter (104) that generates a control signal from the input signal. The reproduction speaker (101) is disposed so as to face the listener. Each of the control speakers (102) is disposed at the periphery of the reproduction speaker (101) without facing the listener. The control points are disposed so as to face the reproduction speaker and the control speakers respectively. The control filter (104) generates a control signal so that the sound pressure of the diffracted sound is reduced more than the sound pressure of the direct sound, which is the reproduced sound that has reached the position of the listener.