Background: Food service staff are integral to delivery of quality food in aged care homes yet measurement of their satisfaction is unable to be performed due to an absence of a valid and reliable questionnaire. The aim of this study was to develop and perform psychometric testing for a new Food Service Satisfaction Questionnaire developed in Australia specifically for use by food service staff working in residential aged care homes (Flinders FSSQFSAC). Methods: A mixed methods design utilizing both a qualitative (in-depth interviews, focus groups) and a quantitative approach (cross sectional survey) was used. Content validity was determined from focus groups and interviews with food service staff currently working in aged care homes, related questionnaires from the literature and consultation with an expert panel. The questionnaire was tested for construct validity and internal consistency using data from food service staff currently working in aged care homes that responded to an electronic invitation circulated to Australian aged care homes using a national database of email addresses. Construct validity was tested via principle components analysis and internal consistency through Cronbach’s alpha. Temporal stability of the questionnaire was determined from food service staff undertaking the Flinders FSSQFSAC on two occasions, two weeks apart, and analysed using Pearson’s correlations. Results: Content validity for the Flinders FSSQFSAC was established from a panel of experts and stakeholders. Principle components analysis revealed food service staff satisfaction was represented by 61-items divided into eight domains: job satisfaction (α=0.832), food quality (α=0.871), staff training (α=0.922), consultation (α=0.840), eating environment (α=0.777), reliability (α=0.695), family expectations (α=0.781) and resident relationships (α=0.429), establishing construct validity in all domains, and internal consistency in all (α>0.5) except for “resident relationships” (α=0.429). Test-retest reliability coefficients ranged from 0.276 to 0.826 dependent on domain, with test-retest reliability established in seven domains at r>0.4; an exception was “reliability” at r=0.276. Conclusions: The newly developed Flinders FSSQFSAC has acceptable validity and reliability and thereby the potential to measure satisfaction of food service staff working in residential aged care homes, identify areas for strategic change, measure improvements and in turn, improve the satisfaction and quality of life of both food service staff and residents of aged care homes.