Conducting effective countermeasure to the vehicle interior noise is important for compatible with the other vehicle performances such as light weight. Operational transfer path analysis (OTPA) was proposed to identify high contributing parts (OTPA reference model) and vibration behaviors (OTPA principal component model) to the interior noise with small man-hours. By using this method, we can determine which parts should be measured intensively. In case we apply the method to a vehicle body panel, the method tells us suitable measuring part of the body panel at the target frequency band. However, if the body panel is excited by a forced vibration from the suspension, we had better to apply countermeasure to the suspension. Then in this study, we applied the OTPA several times to identify which sequential parts from frame, body to interior noise makes the large noise using a simple plate model. In the analysis, both OTPA models (reference model and principal component model) were applied at various part and considered appropriate procedure of OTPA to obtain useful information for finding out the modification target part accurately. Through the verification test, the effectiveness of the proposed procedure was confirmed.