In this paper, the idea of subdivision topology is introduced and a new method of land use factor area description is proposed based on set algebra. The calculation model of the area statistics of the variation of the ground between the features before and after the change is defined by using the principle of the division of algebraic addition. This method can be used to calculate the area of land use factor into a mathematical formula that can be directly quantified, which can be used to describe the set description of the class change statistics in any two years. It provides a good mathematical foundation for the rapid, efficient and accurate analysis of land use change, which has a certain theoretical significance and practical application value for the long time series data analysis.