Background: Biological biomarkers yielded from positron emission tomography (PET) brain scans serve as a pathway to understanding Alzheimer’s disease pathology. PET brain scan data remain limited for populations traditionally under-included in aging research. Objective: The purpose of this qualitative study was to examine participant-identified barriers to PET brain scan consent and characterize participant-informed elements of educational materials needed to facilitate PET brain scan participation among older Black and Latino adults. Methods: Participants (N = 31) were older adults (mean age = 71 years) who self-identified as either non-Latino Black (n = 15) or Latino (n = 16). Each participant took part in a one-time, in-depth individual interview. Researchers analyzed data guided by a Grounded Theory Approach with both Open Coding and Constant Comparative Coding. Results: Four overarching themes emerged across all participants: 1) knowledge limitations; 2) requirements for consent; 3) motivators for participation; and 4) social networks. Within the four themes, there were differences based on participant ethnoracial group. For example, for Theme Three, older Black adults indicated that they would expect compensation for PET brain scan participation. Conversely, older Latinos stated that they would appreciate, but not anticipate, a financial incentive. All participants stressed the importance of written educational materials with subsequent verbal discussions with studystaff. Conclusion: Findings inform the development and implementation of scientifically-relevant and culturally-cognizant engagement approaches, educational materials, and recruitment strategies to increase PET brain scan participation by diverse older adults.