Abstract: Spatial scale integration, the process of integrating different types of data on spatial scale, is one of the core issues in multi-scale GIS research. In order to solve this question, this paper proposes a method which takes the stadia as a measurement of object space scale on the basis of natural principle. The conversion methods between stadia, ratio scale and level scale are also discussed. The"object-form-style" three-tier data structure is used to manage and store multi-scale integrated data. The research vesult shows that: ① Taking the stadia as a measurement of space scale is in accordance with the cognitive pattern; ② spatial scale integration based on stadia is an effective method to solve GIS data model assimilation; ③ the integration and application of spatial scale is a comprehensive problem, which needs the support of key technologies such as spatial scale transformation, multi-scale storage structure, etc.