The invention relates to an electro-optical distance measurement device comprising a signal generator for generating a high-frequency signal, an emitter for sending out measurement light which is subjected to the frequency modulation of the high-frequency signal to an object to be measured, an optical-electric receiving and converting device which receives reflected measurement light reflected from the object to be measured and generates a corresponding high-frequency reflection measurement signal, a phase detector which can carry out mixing processing on the high-frequency signal and a signal processing device used for determining a distance to be measured, wherein the high-frequency signal is input in the phase detector and is mixed with the high-frequency reflection measurement signal in the phase detector to generate a direct current signal, and the direct signal contains phase information for determining the distance to be measured. Since the high-frequency signal and the high-frequency reflection measurement signal which are generated and processed by the electro-optical distance measurement device have the same frequency, the beat interference on a circuit board and the electrical interference among elements in the electro-optical distance measurement device are effectively avoided.