To clarify the relationship between the dozing off during school lessons and life-style habits, this study was conducted by giving a questionnaire to 258 students at Kyoto University of Education. Students who dozed habitually more than twice a week during the lessons accounted for 86.4％. A significant relationship was found between sleeping habits and dozing off. The frequency of dozing was high in students with short sleeping time, and students with late bedtimes. In other life-style habits, students who do not chew their food well and students with little sunlight exposure in the morning dozed the most often.
