Background Dementia-friendly community has been promoted in Macao since 2016. There is no study investigating the understanding of nor attitudes towards dementia among public contact staff in Macao. This study aimed to (i) understand the level of knowledge of dementia, (ii) examine the attitudes towards people living with dementia, and (iii) explore the associated factors of the willingness to help people with dementia symptoms among police officers, bank officers, bus drivers, and building superintendents. Methods A cross-sectional survey was conducted between January and May 2019 using a structured questionnaire. Results A total of 351 valid questionnaires were received. Building superintendents had more knowledge while police officers and bank officers had more positive attitudes. All practitioners were more willing to help people with dementia symptoms when they were on official duty. Participants who had more knowledge about dementia were associated with a higher willingness to help people with dementia symptoms.