Abstract
In Japan, cellular phones have become a kind of wearable computer and Japanese people called them "keitai (denwa) " , literally portable (phones) . Keitai as an information media is necessities of our life. Our main concern is to clarify the mechanism that keitai gives our behavior and decision making. Therefore, we conducted questionnaire survey for utilizing keitai and analyzed obtained data. We also showed an introduction to process for utilizing keitai at disaster.