With a rapid increase in size and complexity of software today, the scope of software testing is also expanding. The efficiency of software testing needs to be improved in order to ensure the appropriate delivery deadline and cost of software development. For improving efficiency of software testing, the test needs to be designed in a way that the number of test cases is sufficient and appropriate in quantity. Test analysis is the activity to refine Application Under Test (AUT) into proper size that test design techniques can be applied to. It is for designing the test properly. However, the classification for proper size depends on individual’s own judgments. This paper proposes a test analysis method for the black box testing using a test category that is the classification based on fault and AUT knowledge.