Abstract: Flower is the reproductive organ of angiosperms. Floral pattern formation is of great scientific significance for the study of plant evolution, morphological development and crop breeding. The data containing 261 microarray data of 79 samples were obtained from The Arabidopsis thaliana Information Resource Center（TAIR） database, and the three-stage core protein-protein interaction networks of flower development in Arabidopsis thaliana were constructed using support vector machine technology. A batch of potential important functional genes related to the flower morphological development and floral organ formation of A. thaliana were developed through functional enrichment analysis, network topology analysis and cluster analysis. By improving the classic ABCD model of flower development, the genetic mechanisms of multi-stage networks of flower development in A. thaliana were initially explained.