The invention discloses a distance measurement method and system based on binocular stereo vision. The method comprises the following steps: acquiring a position relationship between two fixed points; constructing a distance measurement model by using one fixed point as the original point according to the position relationship; and acquiring unknown parameters through easy calibration according to the model so as to realize the distance measurement of a target. The method can enlarge the information amount of infrared-visible images and provide position information of the target by using a heterogeneous source consisting of a thermal imager and a visible CCD (charge coupled device) camera to measure the distance.