Objectives: Handgrip strength (HGS) and muscle mass are strong predictors for dependency in Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL) in community dwelling older adults. Whether this also applies to older hospitalized patients is yet unknown. We studied the association between HGS and muscle mass with ADL and IADL dependency at admission and change of ADL and IADL dependency at three months after discharge in older hospitalized patients. Design: Observational longitudinal inception cohort (EMPOWER) including 378 patients aged 70 years and older. Setting: Four different clinical wards of a university teaching hospital, The Netherlands. Measurements: HGS and muscle mass were measured within 48 hours after admission using hand dynamometry and Bio-electrical Impedance Analysis respectively. ADL dependency was assessed using the Katz score (0-6 points) and IADL dependency using the Lawton and Brody score (0-8 points) within 48 hours after admission and three months after discharge. Results: At admission, lower HGS was associated with ADL dependency in both males and females. Lower muscle mass was associated with ADL dependency in males. Lower HGS was associated with IADL dependency, but only in males. Lower HGS at admission in males was associated with an increase in ADL dependency three months after discharge. Conclusion: In hospitalized older patients, HGS is associated with ADL and IADL and muscle mass measures with ADL in male patients only. HGS should be explored as predictive marker for outcome of hospitalized older patients after discharge.