Objectives: To estimate the proportion of family caregivers assisting older adults during Medicare home health who have an identified need for activity-specific training and identify characteristics associated with caregiver training needs. Design: Nationally representative retrospective cohort study. Setting and Participants: 1758 (weighted n = 8,477,990) Medicare beneficiaries who participated in the National Health and Aging Trends Study (NHATS) and received Medicare-funded home health care between 2011 and 2016. Measures: Older adult and caregiving network characteristics before home health (sociodemographic factors, caregiver assistance, older adult health and function) were drawn from NHATS; characteristics during home health (family caregiver training needs, older adult health and function) were drawn from home health patient assessments. Weighted proportions of family caregivers with an identified need for activity-specific training were estimated. Weighted, multivariable logistic regressions modeled associations between older adult/caregiving network characteristics and family caregivers' identified activityspecific training needs during home health. Results: More than 1 in 3 (35.7%) family caregivers assisting older adults during Medicare home health had an identified training need with at least 1 caregiving activity. Rates of need for training varied widely, from 8.6% among caregivers helping with advocacy to 48.2% among caregivers helping with medical procedures. In weighted analyses that adjusted for older adults' health and function, family caregivers were less likely to have identified training needs when assisting older adults with ongoing disability or who received caregiver assistance before home health admission. Conclusions and Implications: Findings highlight the pervasiveness of family caregivers' training needs, particularly with medically oriented activities, and indicate that escalations in older adults' care needs are linked to caregiver training needs. Therefore, transitions of care may present critical opportunities to connect family caregivers with training resources.