Understanding the disability situation of elderly people in China and its related influencing factors is an important basis for preventing disability and improving the quality of life of elderly people. Therefore, this study is based on data from the 2018 Chinese Longitudinal Healthy Longevity Survey (CLHLS) and uses the Instrumental Activities of Daily Living (IADL) scale to determine the disability of elderly people. SPSS 27.0 was used to analyze the data and perform hypothesis testing to obtain research results. The research shows that: (1) individual characteristics have a significant impact on the disability of elderly people in China; (2) living habits have a significant impact on the disability of elderly people in China; (3) economic status has a significant impact on the disability of elderly people in China; (4) mental health has a significant impact on the disability of elderly people in China. In view of this, it is necessary to take relevant health intervention measures from the perspectives of the elderly themselves, families, and society, strengthen health education and promotion, form good health awareness and living habits, continuously pay attention to the mental health of the elderly, and improve the caregiving ability of family caregivers. In addition, improving policies and social support systems for the elderly, focusing on economic assistance for the elderly, and improving their quality of life can fundamentally reduce the risk of disability.