We analysed two large national surveys conducted in 2001 and 2008 to examine incidence and outcomes of gastroenteritis in older Australians. A case was someone reporting ≥3 loose stools or ≥1 episode of vomiting in 24 h, excluding non-infectious causes. We compared cases arising in the elderly (≥65 years) and in other adults (20-64 years). Elderly people experienced 0·33 [95% confidence interval (CI) 0·24-0·42] episodes of gastroenteritis/person per year, compared to 0·95 (95% CI 0·74-1·15) in other adults. Elderly cases reported less stomach cramps, fever and myalgia than younger cases, and were more likely to be hospitalized, although this was not statistically significant. In multivariable analysis, gastroenteritis in elderly people was associated with travelling within the state (odds ratio 1·35, 95% CI 1·07-1·71). Elderly people were less concerned about food safety than other adults. Older Australians were less likely to report gastroenteritis and experienced different symptoms and outcomes from other adults.