Abstract: Based on the tree data structure, the software code framework automation algorithm called CFAA based on breadth first search (BFS) was proposed in the paper. The algorithm uses the tree data structure to represent scientific computing software architecture, then uses the BFS to traverse all nodes of the tree to generate code framework of software. CFAA enables programmers to focus more on computing software architecture design and optimization, and then automatically generates the code framework. CFAA has been applied to COSINE software development process. The practice proves that CFAA can improve the efficiency of building software framework, while reduce the defect rate of software development.