The 5W1H and interpretive structural modeling (ISM) methods are used to find the hierarchy of factors, the varied characteristics within different research area, and routes of those factors. The value of this approach is a good bridge between qualitative research and quantitative research. The purpose of this paper is to perform mathematical calculations rules based on 5W1H and ISM method structural system. The aims not only could be used to analyze the structural of reachable matrix that produced from 5W1H, but also could be able to deal with the properties of equivalent factors and ring factors by the reducts process to simplify the structure. Finally, an exemplification was applied for
examples.