It is required that Performance Shaping Factors (PSFs) of a trouble event are found using analytic methods such as 5-whys analysis in order to planning the measures preventing the trouble. Further, to grasp the structure of PSFs including background PSFs is needed for taking substantial measures. Our previous study pointed that Interpretive Structural Modeling (ISM) is the relatively easy and logical way of representing the structure of PSFs for site workers. Therefore, we tried to bring in ISM into Root Cause Analysis (RCA). In this regard, a company has been using a RCA method. Although the RCA method enable the description of various trouble factors, the difficulties of grasping the perspective of the trouble has been pointed out. Thus, this study aimed at applying ISM to the RCA method and the site workers in the company having different RCA-work experience tried to the RCA-work using ISM. From the results, we found that using the RCA method applied ISM was possible for site workers and it was advisable to provide manuals including proper advice about deciding PSFs from the trouble factors described in the forms for the RCA method.