Voice enhancement device and voice enhancement method

A voice enhancement device includes: a sound receiving unit configured to receive an audio signal; a vehicle state monitor unit configured to monitor a vehicle state; a noise estimation unit configured to estimate a noise component for each frequency component using a cumulative histogram created by accumulating frequency of power of the audio signal received by the sound receiving unit for each frequency component; and a voice enhancer configured to suppress the noise component for each frequency component estimated by the noise estimation unit in the received audio signal, wherein the noise estimation unit resets the cumulative histogram on the basis of a monitoring result of the vehicle state monitor unit.