As quality of life (QOL) could be influenced by oral status in the elderly, we examined whether chewing ability or number of teeth affected QOL in 80-year olds. A cross-sectional survey included dental examination, chewing self-assessment, and a QOL questionnaire. A total of 823 people who were 80 years old participated in this study. QOL was assessed in terms of satisfaction with physical condition, meals, daily living and social interactions, and with face-scale scores. After adjustment for gender, spouse and activities of daily living, dissatisfaction with social interactions was 3·9 times more prevalent in individuals able to chew four foods or fewer than in those chewing 15. Dissatisfaction with physical condition, meals and daily living, and poor face-scale scores, were 2·7, 2·4, 3·4, and 2·4 times more prevalent, respectively, in subjects chewing four foods or fewer. The number of teeth showed little effect. In conclusion, self-assessed chewing ability but not number of teeth was associated with QOL in 80-year-old subjects.