Objectives: To explore the prevalence of temporomandibular dysfunction (TMD) among working Australian adults and examine whether workplace effort-reward imbalance is associated with TMD. Method: Data were from Australia’s National Survey of Adult Oral Health (NSAOH) 2004-06, a cross-sectional stratified clustered sample of Australian adults. The NSAOH data included information from a Computer Assisted Telephone Interview, self-complete questionnaire and oral epidemiological examination. Data included demographics, socio-economic characteristics, caries experience, diagnostic criteria for TMD, the Perceived Stress Scale (PSS) and a modified version of the Effort-Reward Imbalance instrument (ERI) where ERI ratio is the weighted ratio of workplace effort/reward subscales. Subpopulation analysis for working adults was conducted including complex sample descriptive statistics, bivariate and multivariable logistic regression models. Results: NSAOH had 4014 participants with 2329 (65.1%, SE=1.3%) working adults included in the subpopulation analysis. Among working adults, TMD prevalence was 9.4% (SE=1.0%), which was slightly less than population prevalence (PR=9.9%, SE=0.8%), and was higher for females (PR=12.4%, SE=1.4%), people aged <35 years (PR=11.2%, SE=2.2%) and uninsured (PR=11.8%, SE=1.7%). TMD prevalence was associated with the ERI ratio (OR=2.5, 95% CI: 1.3-4.5) and PSS scores (OR=1.1, 95% CI: 1.0-1.09) in bi-variate associations. In multivariable logistic regression, TMD was associated with being female (OR=2.1, 95% CI:1.3-3.6), university qualified (OR=0.43, 95%CI: 0.21-0.88) and with the ERI ratio (OR=2.63, 95% CI: 1.47-4.72). Conclusion: Greater effort-reward imbalance in the workplace is a psychosocial risk factor for TMD. This finding might need to be considered by clinicians managing TMD patients with need for investigating the efficacy of workplace stress management interventions. Keywords: effort-reward imbalance, work environment factors, temporomandibular dysfunction, national survey, Australia