The invention provides a distance measurement method based on a millimeter-wave radar. The method comprises the following steps that: obtaining the radar signal data of the millimeter-wave radar; according to the radar signal data, obtaining a detection matrix, and setting a distance CFAR (Constant False-Alarm Rat) threshold value, wherein the line of the detection matrix represents distance, andthe row of the detection matrix represents speed; according to the CFAR threshold value, grouping the detection matrix; in each group, comparing data in each row to obtain a maximum value; and outputting the maximum value, and determining a minimum distance between the millimeter-wave radar and an object according to the maximum value. By use of the method, the distance data is distinguished in advance, a situation that the radar can not detect the object when the radar and the object are simultaneously static can be eliminated. Meanwhile, the distinguishing speed for the shortest distance between the radar and the object is greatly improved, and the working performance of the millimeter-wave radar is improved. The invention also provides a distance measurement system based on the millimeter-wave radar, a computer readable storage medium and the millimeter-wave radar, and also has the above beneficial effects.