The checking survey in Open mine is one of the most frequent and important work. It plays the role of forming a connecting link between open mine planning and production. Traditional checking method has such disadvantages as long time consumption,heavy workload, complicated calculating process, and lower automation. Used GPS and GIS technologies to systematically study the core issues of checking survey in open mine.A detail GPS data acquisition coding scheme was presented. Based on the scheme an algorithm used for computer semiautomatic cartography was made. Three methods used for eliminating gross errors from raw data which were needed for creating DEM was discussed. Two algorithms were researched and realized which can be used to create open mine fine DEM model with constrained conditions and to dynamically update the model.The precision analysis and evaluation of the created model were carried out.