A laser radar device for wind measurement comprising: a wavelength-tunable light source configured to emit light with a plurality of different wavelengths; an optical branch coupler configured to divide the light emitted by the wavelength-tunable light source into local light and transmission light; an optical phase modulator configured to apply, to the transmission light, frequency shifts thereby to output modulated transmission light; a wavelength separator configured to perform switching between respective light paths for output, in response to a wavelength of the modulated transmission light; a plurality of optical antennas (14a, 14b, 14n) connected to the respective light paths and having lines of sight corresponding to respective wavelengths of the modulated transmission light, the plurality of optical antennas (14a, 14b, 14n) being configured to emit into space the modulated transmission light output by the wavelength separator, and configured to receive, as received light, backward-scattered light generated from the modulated transmission light in space; an optical heterodyne receiver configured to receive the local light and the received light, and configured to perform heterodyne detection; and a signal processor configured to perform frequency analysis of an output signal of the optical heterodyne receiver to calculate a power spectrum, characterized in that: the optical phase modulator is configured to apply, to the transmission light in a time-division manner, frequency shifts for wavelength discrimination of different shift amounts corresponding to the different wavelengths of the light emitted by the wavelength-tunable light source, and frequency shifts for modulation in which the frequency shifts for modulation do not depend on the respective wavelengths of the transmission light; and the signal processor is configured to calculate peak values appearing at frequencies corresponding to the frequency shifts for wavelength discrimination in the power spectrum, further comprising a semiconductor optical amplifier configured to convert the modulated transmission light into pulses, wherein the optical phase modulator is configured to apply the frequency shifts for wavelength discrimination to rising portions or falling portions of the pulses. a wavelength-tunable light source configured to emit light with a plurality of different wavelengths; an optical branch coupler configured to divide the light emitted by the wavelength-tunable light source into local light and transmission light; an optical phase modulator configured to apply, to the transmission light, frequency shifts thereby to output modulated transmission light; a wavelength separator configured to perform switching between respective light paths for output, in response to a wavelength of the modulated transmission light; a plurality of optical antennas (14a, 14b, 14n) connected to the respective light paths and having lines of sight corresponding to respective wavelengths of the modulated transmission light, the plurality of optical antennas (14a, 14b, 14n) being configured to emit into space the modulated transmission light output by the wavelength separator, and configured to receive, as received light, backward-scattered light generated from the modulated transmission light in space; an optical heterodyne receiver configured to receive the local light and the received light, and configured to perform heterodyne detection; and a signal processor configured to perform frequency analysis of an output signal of the optical heterodyne receiver to calculate a power spectrum, characterized in that: the optical phase modulator is configured to apply, to the transmission light in a time-division manner, frequency shifts for wavelength discrimination of different shift amounts corresponding to the different wavelengths of the light emitted by the wavelength-tunable light source, and frequency shifts for modulation in which the frequency shifts for modulation do not depend on the respective wavelengths of the transmission light; and the signal processor is configured to calculate peak values appearing at frequencies corresponding to the frequency shifts for wavelength discrimination in the power spectrum, further comprising a semiconductor optical amplifier configured to convert the modulated transmission light into pulses, wherein the optical phase modulator is configured to apply the frequency shifts for wavelength discrimination to rising portions or falling portions of the pulses. the optical phase modulator is configured to apply, to the transmission light in a time-division manner, frequency shifts for wavelength discrimination of different shift amounts corresponding to the different wavelengths of the light emitted by the wavelength-tunable light source, and frequency shifts for modulation in which the frequency shifts for modulation do not depend on the respective wavelengths of the transmission light; and the signal processor is configured to calculate peak values appearing at frequencies corresponding to the frequency shifts for wavelength discrimination in the power spectrum, further comprising a semiconductor optical amplifier configured to convert the modulated transmission light into pulses, wherein the optical phase modulator is configured to apply the frequency shifts for wavelength discrimination to rising portions or falling portions of the pulses.