Background The longevity of the world population can contribute to an increase in hospitalizations and, consequently, to the emergence of functional limitations, resulting in the need for family caregivers. Hospitalized older adults may become dependent and require more care, increasing the burden on family caregivers. Thus, the nursing team in the hospital environment faces a new situation: an increase in the number of older adults occupying hospital beds and the presence of their family caregivers. Objective We aimed to analyze the association between the demographic variables of interest and the self-rated health of family caregivers and to describe the functionality of older adults hospitalized in a university hospital in the Amazonian context. Methods This cross-sectional, quantitative, exploratory, and descriptive study was carried out through individual interviews with 98 interviewees, divided into 49 family caregivers and 49 older adults hospitalized in the surgical clinic sector of a university hospital in Brazil between February and March 2023. Demographic data and health conditions were collected from family caregivers, and to describe the functionality of hospitalized older adults, the Barthel Index was applied. Descriptive (frequency and percentage) and inferential analyses were used, and the student t test was applied. The significance level of 5% was adopted. Results Among the 49 family caregivers, the majority were women (n=40, 81.6%) with an average age of 46.9 (SD 13.3) years. Most were single (n=28, 57.1%) and had completed an average level of education (n=26, 53.1%). Additionally, 25 (51%) caregivers were caring for their parents. Regarding health conditions, respondents self-assessed their health as good (25/49, 51%; P=.01), and they considered that their health status was not affected by the provision of care (36/49, 73.5%; P=.01). There was a significant association between demographic variables (ie, gender, age, and education) and self-assessment of family caregivers (P=.01, P=.01, and P=.04, respectively). Of the 49 older adults hospitalized, the majority (n=31, 63.2%) were men, with a mean age of 69.2 (SD 7.12) years. Regarding the assessment of functionality, most older adults were classified as having mild dependence on care (n=23, 46.9%), specifically in the age group between 60 and 69 years (21/49, 67.8%). Conclusions The data revealed that female gender, age, and education of family caregivers contributed favorably to the provision of care to hospitalized older adults with a lower degree of functional dependence. It is important to emphasize that during the older adult’s hospitalization, the family caregiver should not be seen as a delegation of responsibilities or as a complement of human resources to assist in their recovery. Health professionals need to implement assertive interventions so that the family caregiver functions as a therapeutic resource.