The cut-off value of tongue pressure on the ability to perform activities of daily living could be a useful indicator for preventing deterioration of the ability to perform activities of daily living. This study aimed to investigate the relationships among swallowing function, including tongue pressure, nutrition status, and physical function and ability to perform activities of daily living and establish a cut-off value in hospitalized old-old and very old patients. Methods: A total of 98 hospitalized patients aged ≥ 75 years were recruited in this cross-sectional study. Swallowing function (tongue pressure and Dysphagia Risk Assessment for the Community-dwelling Elderly), nutrition status (body mass index, albumin, and Mini Nutritional Assessment Short Form version), physical function (timed up and go test), and ability to perform activities of daily living (Barthel index) were measured. Patients were divided into two groups based on the ability to perform activities of daily using Barthel index (Group 1, high ability, and Group 2, low ability).