Abstract: Over the last decade，natural resource exploitation and utilization expands constantly and the economics of urban and rural develop rapidly.The frequency of flood disasters and the resulting losses are increasing.Rapid，accurate and scientific simulations to predict the impact scope of flood disasters are of great significance on the flood control and disaster mitigation.According to the hydraulic characteristics of flood routing，this paper does a deep research and a thorough discussion of the grid modeling based on digital earth，“volume method” flood submerged area calculations，as well as the scope expanded successive incremental recursive algorithm.Finally，the digital earth based position-independent flood routing model and its visualization are realized through the above methods.