Aim This study aimed to explore the perceptions of dementia experts on support for people with dementia (PWD) and their families, considering PWD's vulnerability regarding COVID-19 prevention. Methods A collaborative qualitative study was conducted, involving Hiroshima University, the Japan Geriatrics Society, the Japan Society for Dementia Research, and the Japanese Psychogeriatric Society. An anonymous, self-reported questionnaire survey was sent to dementia experts from 456 medical centers for dementia in Japan. The responses were categorized in a qualitative inductive manner. Results A total of 214 experts from 119 centers responded (facility recovery rate: 26.1%). Four core themes emerged from the data analysis. Of these themes, three were related to support for infection prevention and related issues and response to infection: (i) support for continuation of daily life while preventing infection; (ii) support to mitigate the unfavorable effects of infection prevention measures; and (iii) decision-making support and treatment for infected PWD. The remaining theme, (iv) community building for PWD living together, was extracted as a basis for facilitating themes (i) to (iii). Furthermore, in each theme, the roles of medical and long-term care facilities, administration, and the need for community collaboration were identified. Conclusions Dementia experts strongly felt the need not only for short-term support to prevent the spread of infection to PWD and their families during the pandemic, but also for long-term support to enable them to maintain their daily lives and mitigate the impact of infection prevention measures. Geriatr Gerontol Int 2021; center dot center dot: center dot center dot-center dot center dot.