Abstract: The construction of land-use database is very important and helpful for advancing the level of scientific programming and reasonable exploitation and utilization of land resources as well as for making the information of state-land resources standardization and scientificalness. However , the problemes of the construction efficiency and accuracy cann’t be neglected. The paper tries its best to discuss the key technique in the process of the database construction such as the key technique to establish mathematical foundation, selection of vectorization method, disposal of topology-fragment polygon , the method of quality control and so on, which provide the realistic significance for the Land-use database construction in future.