The Macao Dementia Policy was recognized by Alzheimer Disease International as the 27th globally and one of the highest stage 5 to develop dementia friendly community and primary health professionals are in a pivotal position to enhance community-based dementia prevention and care quality. This study aimed to investigate the knowledge, attitude and preventive practice on dementia care among primary health professionals in Macao. A specially designed 30-item questionnaire was developed and validated for the study. The Content Validity Index (CVI) and Cronbach’s α of the questionnaire were 0.973 and 0.808. The questionnaires were distributed to all 375 primary health professionals from 8 Health Centers throughout Macao and 234 valid questionnaires (62.4%) were returned. The score for dementia care knowledge was 87.02±14.01; attitude was 69.52±5.83; preventive practice was 77.88±13.18, of which doctors (79.89±13.77) was significantly higher (t=2.29, p=0.023) than nurses (75.91±12.33). There were positive relationships between preventive practice and attitude (r=0.163, p=0.014), and age (r=0.212, p=0.002), and a negative relationship between knowledge and age (r=−0.139, p=0.040). These findings have significant implications that most primary health professionals in Macao had sufficient knowledge, a positive attitude and appropriate preventive practice on dementia care. However, enhanced dementia education to improve knowledge and preventive practice was a strong agenda for the training for senior staff and nurses.