PURPOSE: The impact of oral health status on Taiwanese adults' quality of life has not been measured definitively. This study evaluated the effects of oral health-related variables on quality of life among adults in Taiwan. METHODS: A cross-sectional study design with secondary database analysis was adopted. Information about oral health-related variables in adults aged 18-64 years was collected from the National Health Interview Survey and quality-of-life data from the Short-Form Health Survey (SF-36). Univariate and multivariate regression analysis was used to determine risk factors for oral health and associations between oral health and eight domains of quality of life defined by the SF-36. RESULTS: Gender (P < 0.001), marital status (P < 0.001), monthly income (P < 0.001), disease history (P < 0.001), betel nut chewing (P < 0.001), oral hygiene (P < 0.001), oral health status (P < 0.001), and dental care utilization (P = 0.001) had significant effects on general health as an aspect of quality of life; gender (P < 0.001), marital status (divorced, P < 0.001), income level (20,000-80,000 NTD, P < 0.001), disease history (P < 0.001), oral hygiene, oral health-related food choice limitations (P < 0.001), and dental care utilization (P < 0.001) had significant effects on general mental health. Subjects who practiced dental self-care with tooth brushing had significantly higher social functioning scores than those who did not (P < 0.001). Significant differences were also found in scale items for physical functioning, role limitations due to physical health, bodily pain, vitality, and role limitations due to emotional problems (all P < 0.001). CONCLUSIONS: Demographic (i.e., age, gender, and marital status and income levels) and oral health-related factors (i.e., oral hygiene, dental visits, disease history, and lifestyle factors such as cigarette smoking, alcohol use, and betel nut chewing) are all significantly associated with oral health-related quality of life in Taiwanese adults.