Caregivers provide essential support for the growing population of older adults living in the United States, including physical assistance with activities of daily living, care coordination, and financial support. While many caregivers experience great benefits from their caregiving role, the negative consequences of caregiving, including caregiver burden, have been widely described across years of research. Among older adults living with dementia, these demands on caregivers can be even more substantial. One method of measuring the extent of the support provided by caregivers is caregiving intensity, measured by the monthly hours spent on caregiving responsibilities. While the direct relationship between caregiving intensity and caregiver burden has been described in the literature, less is known about potential mediating factors on this relationship, such as caregiver social engagement, between caregivers of persons living with and without dementia. Using data from linked National Health and Aging Trends Study and National Study of Caregivers survey datasets following a nationally representative sample of older adults and their caregivers (N=1,642), this observational, cross-sectional study aims to examine the relationships between caregiving intensity, caregiver burden, and caregiver social engagement. This study describes (1) the association between caregiving intensity and caregiver burden in caregivers of older adults overall and among those caring for an older adult living with dementia, (2) how the operationalization of caregiving intensity measured by monthly hours spent on ADL-related caregiving responsibilities affects the relationship between caregiving intensity and caregiver burden, and (3) the indirect effect of caregiver social engagement on the relationship between caregiving intensity and caregiver burden. Informed by the Pearlin Stress Process Model, this study uses multivariable logistic and ordinal logistic regressions to describe the relationship between caregiving intensity and caregiver burden. Mediation analyses of primary caregivers of older adults (N=1,051) describe the indirect effect of caregiver social engagement on the relationship between caregiving intensity and caregiver burden using structural equation modeling. This study finds that overall, caregiving intensity is significantly associated with increased odds of caregiver burden after controlling for patient and caregiver characteristics. Furthermore, this association is not maintained across all domains of caregiver burden when caregiving intensity is operationalized using ADL-related caregiving intensity. Finally, this study identifies caregiver social engagement as a statistically significant mediator on the relationships between caregiving intensity and physical and financial burden. Addressing the growing challenge of caregiver burden will require a multidimensional approach to caregiver solutions, including caregiver social engagement, involving the joint support of clinical, public, and private systems.