BackgroundDementia is a global public health priority. Many modifiable factors have been shown to influence the development of dementia, but these factors are not adequately known by the general public. This study aimed to assess public awareness of the factors that are associated with dementia in China.MethodsA cross-sectional study was conducted from May to October 2019 using an Internet-based questionnaire. Data on basic sociodemographic characteristics were collected, and the knowledge of risk and protective factors for dementia was investigated. Logistic regression analysis was performed to compare levels of the knowledge of factors associated with dementia across populations with different demographic characteristics.ResultsData from 3338 respondents were analyzed. The percentages of participants who accurately identified the risk factors of dementia were follows: 84.24% for negative affect, 65.07% for alcohol use, 56.68% for smoking, 48.74% for hypertension, and 42.66% for diabetes. The percentages of participants who accurately identified the protective factors for dementia were follows: 90.00% for exercise, 84.69% for social activity, 80.92% for intelligence games, 74.45% for reading, and 6.14% for antihypertensive or hypolipidemic drugs. The majority of Chinese people correctly recognized the role of lifestyle factors in the development of dementia but not medical factors. The levels of knowledge of the factors associated with dementia were significantly distinct across populations with different characteristics. The following sociodemographic characteristics were associated with more comprehensive knowledge of dementia risk and protective factors: women, young age, high education levels, nonmanual jobs, and contact with patients with dementia.ConclusionsPublic awareness and knowledge of risk and protective factors for dementia in China are still insufficient. More efforts are needed to publicize information to reduce the risk of dementia.