Objectives We aimed to investigate the relationship between the ability to press Process Lead (PL) in the oral cavity and the tongue pressure and recommended diet form for elderly individuals in nursing homes, using PL normalized physical properties. Design Cross-sectional observation study. Setting Geriatric facilities. Participants A 100 elderly individuals aged between 67–96 years. Measurements PL was pressed between the tongue and palate to evaluate its deformation. The thickness was set at 6, 9, and 18 mm. The tongue pressure was measured with a JMS tongue pressure manometer. The number of chewing cycles until an 18-mm thick PL was first swallowed was measured (PL chewing test). The diet was set to level 4, and the recommended form was evaluated by video endoscopic evaluation of swallowing (VE). The results of the PL pressing test and correlations between PL chewing test, tongue pressure, and diet level were statistically examined. Results The tongue pressure was significantly decreased in groups that could not press the PL. The PL pressing test and recommended diet form showed a significant correlation, and the elderly with difficulty in pressing the PL had a lower diet level. In addition, the diet level decreased with decreased PL chewing test performance in those without molar occlusion. Conclusions The PL pressing and chewing tests may aid in ascertaining the appropriate diet level. In the future, we would like to verify the usefulness of these tests in determining the diet level of elderly people requiring long-term care at the time of entering the facility.