Objectives. To estimate the prevalence rates of Alzheimer's disease and related dementias (ADRD) and their risk factors in the transgender population and compare the rates to those in cisgender adults. Methods. We identified 1784 transgender adults in the linked electronic health records and claims data between 2012 and 2020 from the OneFlorida Clinical Research Consortium. We calculated the prevalence of ADRD and ADRD risk factors for the transgender and matched cisgender control adults. Results. The prevalence of ADRD was higher in the transgender adults compared with the cisgender control adults. Overall, the prevalence of ADRD risk factors was significantly higher in the transgender adults than the cisgender controls for 11 out of the 13 risk factors, with the only exceptions being traumatic brain injury and visual impairment. Conclusions. Transgender adults are at significantly higher risk for ADRD than cisgender adults. Our study highlights the urgent need for more research on the unique ADRD risks among the aging transgender and larger sexual- and gender-minority populations. (Am J Public Health. 2022;112(5):754-757. https://doi.org/10.2105/AJPH.2022.306720).