Background: Older caregivers of older patients with cancer are at high risk for adverse physical and psychological outcomes. Performing a caregiver geriatric assessment (GA) may help identify caregivers at increased risk of adverse outcomes and guide supportive care strategies. In this study, we aimed to determine the feasibility of a GA to evaluate age-related conditions, and physical and emotional health of both patients and caregivers. Methods: Caregivers aged 65+ and patients aged 65+ with diagnosis of cancer receiving a new line of cancer treatment and caregivers aged 65+ were recruited (Goal 60 dyads; current N=40). Patient and caregiver physical and emotional health was captured using the GA which included assessment of physical function (activities of daily living [ADLs], instrumental activities of daily living [IADLs], Short Physical Performance Battery [SPPB], fall history), comorbidity, psychological health (Geriatric Depression Scale [GDS], General Anxiety Disorder-7 [GAD-7]), cognition (Montreal Cognitive Assessment [MOCA] or Blessed Orientation Memory Concentration [BOMC]), Social Support (Older Americans Resources and Services [OARS] Social Support), polypharmacy, nutrition, caregiver Environmental Mastery, and Modified Caregiver Strain Index. Results: Of 40 dyads who have consented, 17 dyads (42%) completed the GA, 14 dyad GAs are pending (35%), eight have withdrawn (20%), and one was lost to follow-up (2.5%). Mean time for caregivers to complete self-reported GA assessment was 47 minutes (range 20-120 minutes) and return to study staff was 5 days (range 0-22 days). Caregivers had mean age 78 years (range 65-85), 100% white, 94% female, and 94% spouses. Caregivers had high prevalence of age-related conditions, including comorbidities (mean 3.7), impairments in ADLs (24%), IADLs (31%), and physical function (55%). More patients than caregivers screened positive for depression (29% vs 12%) and anxiety (17% vs 6%). Caregivers reported high mastery (Ryff subscale, mean 38, range 26-49) and low strain (4.4, range 0-16). Conclusions: The GA is feasible to use in older cancer caregivers to help identify aging related conditions that may influence caregiving ability. Future work should identify how GA in older cancer caregivers can be used to identify intervention strategies to optimize caregiving abilities and improve outcomes in both older adults with cancer and their caregivers. Clinical trial information: NCT05244915.