Provided are a hearing aid, signal processing method, and program that enable TV sound to be made easier for a hearing aid user to hear when wishing to watch TV, and a person's voice to be made easier to hear when wishing to converse with that person. A hearing aid (100) is provided with an other-person's speech detection section (150) that detects speech of a speaker other than the wearer using detected sound source direction information, an own-speech detection result, and a TV sound detection result, and a per-sound-source frequency calculation section (160) that calculates the frequency of each sound source using an own-speech detection result, TV sound detection result, other-speaker's speech detection result, and sound source direction information. A scene determination section (170) determines a scene to be a “conversation scene,”“TV viewing scene,” and “‘TV viewing while . . . ’ scene” using sound source direction information and the per-sound-source frequency, and an output sound control section (180) controls hearing of the hearing aid (100) according to a determined scene.