Aiming at the problem that traditional optical non-contact measurement is easy to be influenced by the environment with small measurement range and depends on laser,the method of non-contact measurement based on the principle of conoscopic holography is presented,which makes full use of its characteristics of large measuring range,high resolution, high precision,and good adaption to the environment.Based on the principles of c onoscopic holography measurement,a holographic system suitable for distance measurement is designed ,which an acquire object′s moving distance from the fringe variation,and the relationship between them is deduce d.To solve the problems of fringe image speckle,the uncertainty of fringe center and the obscureness fringe image,the corresponding image processing method and local fringe search method are put forward,which choose clear and smooth fringe region for analysis and calculation,through which we can calculate the variation of fringe width,and thus obtain the d istance.The conoscopic holography distance-measurement system is set up,and the experimental results show that t he measuring error of the conoscopic holography system is less than 10μm compared with the laser interf erometer,which can satisfy measurement demand.