Four studies were carried out to examine the following problem concerning maintenance and improvement of the Activities of Daily Living of the elderly. The subjects are all institutionalized elderly. 1) The first study was to examine the transition of three items: the intake of zinc, the serum zinc concentration and the hematological consistent. It also investigated the hematological consistent that correlate with the serum zinc values. 2) The second study was to examine the relationship between the zinc nutritional status and the factors associated with serum zinc concentration: body mass index (BMI), the level of care, the grade of bedriddenness, and the grade of cognitive function. 3) The third study was to examine relationship, using the Geriatric Nutritional Risk Index (GNRI), between the zinc nutritional status and the activities of Daily Living (ADL). 4) The fourth study was to examine evaluation by GNRI, using BMI and circumference (CC). The obtained results from the four studies are summarized as follows: 1) The Activities of Daily Living of disabled elderly was influenced by the nutritional zinc status. The increasing the nutritional zinc status improved the nutritional status of protein and iron, and contributed to the maintenance and improvement of the Activities of Daily Living of the elderly. 2) Geriatric Nutritional Risk Index proved to be an appropriate an indicator of the nutritional zinc status and Sarcopenia. Thus it may be concluded of that this index is a reliable tool in the nutritional care management.