Abstract: There are four phases in structural testing: Static analysis, path selection, case generation, and dynamic analysis. The“ hierarchical tree” concept is proposed to represent the structure of a program which is written in a structural programming language,so that best use can be made of the advantage of the language. Based on this concept, an automatic method called Branch Cutting is proposed to generate a path cover, which is to be used in the second phase when testing a program. The strong points of this method is the simplicity and flexibility.