Objective: The paper attempts to analyze the “crowding-out” effect of long-term care insurance (LTCI) on intergenerational support from children to parents and its mechanisms. Methods: Based on four waves of panel data from the China Health and Retirement Longitudinal Study (CHARLS) from 2013 to 2020, a difference-in-differences (DID) model was employed to empirically examine the policy effects and mechanisms of LTCI on intergenerational support within families. Results: The implementation of LTCI significantly reduced both financial and caregiving support provided by children to their parents. Mechanism analysis revealed that LTCI decreased seniors' economic dependence on their families, thereby reducing the intergenerational support from their children. With the "exchange motivation", children were less inclined to offer financial assistance to parents. Heterogeneity analysis indicated that the impact of LTCI on intergenerational caregiving was more significant for female seniors, individuals with difficulties in daily activities, and those with poor mental health. Conclusion: LTCI can reduce the burden of intergenerational support and caregiving time within families, thereby releasing household labor. It is recommended to gradually expand the coverage of LTCI policies and diversify the payment items of LTCI policies to solve the problem of children supporting their parents.