Karst is one of the common geological disaster in engineering construction, which threatens the design and construction of Karst area engineering. According to the results of the Donghuangshan international town, it is revealed that the main Karst is covered bead-like karst cave, which is mainly distributed along the Machuan River and its tributaries in a strip. On the basis of summarizing the characteristics of Karst development in the study area, the controlling factors of karst development are fully considered in this paper, selection of six influencing factors : formation lithology, borehole hole rate, thickness of overburen, soil structure, depth of ground water level, distance from the surface river, the risk assessment model of karst development in Donghuangshan international town is constructed by the method of fusion of GIS and AHP. The area of research is predicted and evaluated. The results show that the karst high development area is mainly concentrated in the middle and the north part of the town, and the area is about 0.4 km², which is about 5% of the total area of the study area. According to the situation of borehole exposure, 11 boreholes of karst cave are located in the dangerous area in the Evaluation partition map, and the degree of fit is highly, which indicates that the karst development risk assessment model constructed is consistent with the reality. The research results have certain guiding significance for the planning and construction of the infrastructure of Donghuangshan international town.