According to embodiments, a biosignal measuring device includes a driver, an electric signal acquirer, a voltage signal generator, and an amplifier. The driver drives one or more light emitting elements to emit an optical signal having a light intensity that varies periodically. The electric signal acquirer acquires an electric signal corresponding to the amount of light of the optical signal reflected off the inside of a biological body, or corresponding to the amount of light of the optical signal transmitted through the biological body. The voltage signal generator outputs a voltage signal from which a frequency component which is equal to or lower than a predetermined frequency contained in the acquired electric signal has been removed. The amplifier amplifies the voltage signal and outputs an amplified signal.
