An acoustic signal processing device includes: a front signal processor which generates first L and R signals by performing signal processing on a first signal which is a front channel signal; a first adder which generates a fourth signal which is a left channel signal by adding the first L signal and a second signal which is a left channel signal; and a second adder which generates a fifth signal which is a right channel signal by adding the first R signal and a third signal which is a right channel signal. The front signal processor generates the first L and R signals by signal processing in which the first signal is distributed and placed at predetermined positions when the first signal is a dialog signal, and distributed and placed at positions different from the predetermined positions when the first signal is not a dialog signal.