A sound signal processing device, a sound signal processing method, and a sound signal processing program can remove echo signals included in input signals from a plurality of microphones with a simple circuit configuration are provided.
The present device 1 includes an output part 20 that outputs a reception signal s2, an input part 30 that combines signals input from each of a plurality of microphones 3 and generates a transmission signal s4, wherein the microphones 3 collect an echo component of the reception signal and voice of a speaker and generate an echo signal es corresponding to the echo component and a sound signal s1 corresponding to the voice of the speaker, a removal signal generator 70 that generates a removal signal s5 removing the echo signal included in the transmission signal based on a filter coefficient F, a controller 50 that calculates the filter coefficient, and a removal part 80 that generates an echo removal signal s6 based on the transmission signal and the removal signal. The controller calculates individual filter coefficients k corresponding to the respective microphones, and calculate the filter coefficient by combining the individual filter coefficients.