This research divides oral health status into two parts: clinical disease and patients' subjective perceptions, and then discusses what impact these two items have on the health-related quality of life. A total of 1600 elderly persons, over 65 years old, were sampled as the research target. The overall response rate was 71·62%. SF-36 was used to measure the health-related quality of life, Oral Health Impact Profile (OHIP) was used to measure individuals' subjective perception of their oral health status, and the number of natural teeth was considered as the clinical issue. There are 12 items which affect quality of life in the physical aspect, namely: OHIP score; age; gender; weekly frequency of social activities and interactions; financial status; physician visits per month on a regular basis; hospitalization during the last 6 months; arthritis, rheumatism, cardiovascular disease or diabetes; abnormal IADL patients; and the satisfaction level of current lifestyle. Factors affecting quality of life (i.e. mental aspects), are few, including: OHIP score, gender, education level, weekly frequency of social activities and interactions and satisfaction level of current lifestyle. The results indicate that individuals' subjective perceptions of their oral health status had a greater impact, than did the clinical issue, on their health-related quality of life. The outcomes and findings derived from this research may provide alternative perspectives for professionals, so that they may be more careful concerning individuals' subjective perceptions.