Introduction Informal caregiving during hospitalization of older adults is significantly related to hospital processes and patient outcomes. Studies in the home settings demonstrate that ethno-cultural background is related to various aspects of informal caregiving; however, this association in the hospital setting was insufficiently researched.Objectives Our study looked for differences between ethno-cultural groups in the amount and kind of informal support they provided for older adults during hospitalization.Methods This study is a secondary data analysis of two cohort studies conducted in Israeli hospitals. Hospitalized older adults were divided into three groups: Israeli-born and veteran immigrant Jews, Arabs, and Jewish immigrants from the Former Soviet Union (FSU).Results Informal caregivers of “FSU immigrants” stayed less hours during the day in both cohorts, were less present during the night in study 1, and provided less supervision of medical care in study 2, in comparison to the two other groups. Findings from study 1 also suggested that informal caregivers of “Arab” older adults were more likely to stay during the night in comparison to the two other groups.Conclusion Ethno cultural groups differ in terms of the patterns of caregiving older adults during hospitalization. Health care professionals should be aware of these patterns and the cultural norms that are related to caregiving practices for better cooperation between informal and formal caregivers of older adults.