Abstract: Automatic map generalization is a complex problem which includes much data analysis. And knowledge is needed in data models operations and their relations. Thus, it is necessary to analyze the method of decomposement and operators set of automatic map generalization for solving this complex problem. In this paper, with respect to the essential characteristic of objective of map generalization and its self-rules, the problem of map generalization is decomposed, and a complete operators set of map generalization is given, based on the analysis of existent operators sets of map generalization. The relationship and rank of operators are discussed.