A photoacoustic measurement device reducing artifacts caused by photoacoustic waves generated at a surface portion of a subject on which measurement light is incident, and a signal processing method thereof are obtained. A photoacoustic measurement device includes region discrimination unit that discriminates an artifact generation region and an artifact non-generation region in a photoacoustic image on the basis of a positional relationship between a light emitting portion and an acoustic wave detection portion, and filter unit that performs a first filtering process on a first photoacoustic wave detection signal corresponding to a photoacoustic image of the artifact non-generation region and performs a second filtering process on a second photoacoustic wave detection signal corresponding to a photoacoustic image of the artifact generation region. The second filtering process includes further reducing the photoacoustic wave detection signal in a frequency range lower than a predetermined frequency as compared with the first filtering process.
