The invention relates to a frequency-beating device for laser frequency measurement, which belongs to the technical field of photoelectrons and comprises a first collimation positioning aperture diaphragm, a second collimation positioning aperture diaphragm, a third collimation positioning aperture diaphragm, a fourth collimation positioning aperture diaphragm, a fifth collimation positioning aperture diaphragm, a sixth collimation positioning aperture diaphragm, a seventh collimation positioning aperture diaphragm, an eighth collimation positioning aperture diaphragm, a first totally-reflecting mirror, a second totally-reflecting mirror, a third totally-reflecting mirror, a fourth totally-reflecting mirror, a first half-wave plate, a second half-wave plate, a polarization light-splittingprism, a Glan prism, a raster, a silver mirror, a ninth adjustable-aperture aperture diaphragm, a gathering lens, an avalanche diode, a low-noise amplifier, a band-pass filter, a one-dimensional mobile platform and a vibration isolation optical panel. The frequency-beating device disclosed by the invention is easy to regulate and maintain a frequency-beating optical path, and can achieve the purpose of improving a signal to noise ratio of a frequency-beating signal so as to be convenient for reading by using a frequency counter and keeping the high signal to noise ratio frequency-beating signal for a long time.