This study examined sitting time, knowledge and intentions to change sitting time in older adults. An online survey was completed by 494 Australians aged 65+. Average daily sitting was high (9.0 hrs). Daily sitting time was the highest during TV (3.3 hrs), computer (2.1 hrs) and leisure (1.7 hrs). A regression analysis demonstrated that women were more knowledgeable about the health risks of sitting compared to men. The percentage of older adults intending to sit less were the highest for TV (24%), leisure (24%) and computer (19%) sitting time. Regression analyses demonstrated that intentions varied by gender (for TV sitting), education (leisure and work sitting), BMI (computer, leisure and transport sitting) and physical activity (TV, computer and leisure sitting). Interventions should target older adults' TV, computer and leisure time sitting, with a focus on intentions in older males and older adults with low education, those who are active and those with a normal weight.