Abstract: This paper explains how to use GPS technique to monitor the slope deformation in Jinchuan open pit mine. The authors introduce the conditions of mine simply. The main topic is how to choose the monitoring basic points; how to measure WGS 84 coordinate of the basic points; how to lay out the network for deformation observation; to collect GPS data, to deal with the result and its quality; and how to carry out the conversion of coordinate system, etc. Diplacements of some four order triangulation points and other control points have been back calculated from GPS observation data. These results are fit for an explanation of the physical properties deformation. Finally, the authors point out that the GPS technique has certain advantages for the mine field measurement.