Objectives This study investigated whether and to what extent constructs of the protection motivation theory of health (PMT)—threat appraisal (perceived vulnerability/severity) and coping appraisal (response efficacy and self-efficacy)—are related to telehealth engagement during the COVID-19 pandemic, and how these associations differ by race/ethnicity among middle-aged and older Americans. Methods Data were from the 2020 Health and Retirement Study. Multivariable ordinary least-squares regression analyses were computed adjusting for health and sociodemographic factors. Results Some PMT constructs are useful in understanding telehealth uptake. Perceived vulnerability/severity, particularly comorbidity (b = 0.13, 95% confidence interval (CI) [0.11, 0.15], p < 0.001), and response efficacy, particularly participation in communication via social media (b = 0.24, 95% CI [0.21, 0.27], p < 0.001), were significantly and positively associated with higher telehealth uptake during the COVID-19 pandemic among middle-aged and older Americans. Non-Hispanic Black adults were more likely to engage in telehealth during the pandemic than their non-Hispanic White counterparts (b = 0.20, 95% CI [0.12, 0.28], p < 0.001). Multiple moderation analyses revealed the significant association between comorbidity and telehealth uptake was similar across racial/ethnic groups, whereas the significant association between social media communication and telehealth uptake varied by race/ethnicity. Specifically, the association was significantly less pronounced for Hispanic adults (b = −0.11, 95% CI [−0.19, −0.04], p < 0.01) and non-Hispanic Asian/other races adults (b = −0.13, 95% CI [−0.26, −0.01], p < 0.05) than it was for their non-Hispanic White counterparts. Conclusion Results suggest the potential of using social media and telehealth to narrow health disparities, particularly serving as a bridge for members of underserved communities to telehealth uptake.