Abstract: By making use of the data of the Chinese Longitudinal Health Longevity Survey (CLHLS) of 2014, this paper conducts an empirical analysis of the impact of informal nursing on the use of housekeeping services and the use of nursing home services by means of the instrumental variable method. In addition, it analyzes for the first time the impact of the degree of disability on the relationship between informal nursing and formal nursing. The results of the study show that there is a significant substitutive relationship between informal nursing and formal nursing, and this substitutive relationship is not affected by the individual heterogeneity of the degree of disability of the elderly. This shows that the state policies of encouraging and supporting family care for the older can effectively promote the demand for informal nursing services and reduce the burden of families and the society.

Key words: informal nursing; formal nursing; the extent of disability; the substitution effect