Background: In December 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), or COVID-19, raised worldwide concern. Since then, the COVID-19 pandemic has negatively influenced health and wellness across the globe and caused nearly three million deaths. This study focuses on informal caregivers of people with dementia, a disease that affects about 50 million older adults worldwide and requires much caregiving support. Objective: Examine the current literature on the impact of COVID-19 on the health and well-being of informal caregivers for people with dementia. Method: This rapid review was conducted across five electronic databases for quantitative and qualitative articles published through March 15, 2021. Results: The 10 studies included in this review reported quantitative descriptive data from across the globe; however, no studies existed from the U.S. or East Asia countries. All of the studies examined the psychological rather than physical impact of COVID-19 and highlighted risk and protective factors in the areas of psychosocial (resilience, neuropsychiatric, and social isolation), sociodemographic (gender and education), and environmental (home confinement, living arrangement, and dementia stage). Conclusion: COVID-19 has had a considerable negative impact on the psychological well-being of informal caregivers of people with dementia, namely causing more depression and anxiety than pre-pandemic.